What you see depends on what time of year you visit.

There's two kinds of team: club and inter-county. Club games are normally 60 minutes; inter-county 70 minutes:

Most participants play for clubs. You drive around Ireland and see GAA clubs everywhere. Club competitions start in September (maybe late August) and run til December or January

Inter-county contest is more élite, more of a spectator sport. Higher quality but less participatory. The best players from each of Ireland's 32 counties compete in county-v-county matches. This is January to August. That's why in my first comment, we're seeing the club finals wrap up, and the first glimmer of inter-county season.

Aug/Sept-Oct is club county championships

The clubs compete to find who's the best club in each county. Examples of the format and timing –

• https://en.wikipedia.org/wiki/2023_Tyrone_Senior_Football_Championship

• https://en.wikipedia.org/wiki/2023_Dublin_Senior_Football_Championship

• https://en.wikipedia.org/wiki/2023_Kilkenny_Senior_Hurling_Championship

Rarely be televised tbh, clubber.ie has videos and GAAgo.ie might have a few finals. Video production quality might not be what you're used to; filming sporting events is expensive.

Oct/Nov-Jan is club provincial and all-Ireland club championships

The champ-clubs of each county compete to win their provinces (Ireland has 32 counties, 4 provinces). And then the four provincial champions face off in semi-finals and the All-Ireland club final. (A complication: although Ireland has four provinces – Leinster, Munster, Connacht, Ulster – sometimes they get mashed together for GAA purposes. So Galway is in Connacht geographically but sometimes is in Leinster GAA contests.)

• 2023–24 All-Ireland Senior Club Hurling Championship – 5 November 2023 – 21 January 2024

• 2023–24 All-Ireland Senior Club Football Championship – 21 October 2023 – 21 January 2024

Gaago.ie would often have these .

Jan-April is inter-county Leagues

Leagues of inter-county teams, and a few other inter-county contests like the Walsh Cup I mentioned in my first comment.

• 2024 National Hurling League – 3 February-6/7 April 2024 – Wikipedia explains the format pretty well there. Another complication: while Ireland has 32 counties, the GAA recognises other 'counties' in the sense of teams that can compete, so London, Lancashire and Warwickshire are 'counties' for this purpose. You also see County New York or County Canada pop up sometimes.

2024 National Football League (Ireland)

Why do we have two inter-county contests, you may ask? One Jan-April and then another one? Bloody good question. Nobody can make sense of it. Maybe so that Mayo can win something lol. You hear podcasters and people talk about scrapping the League, focusing on the actual All-Ireland

April-July/Aug is the big one

All-Ireland Hurling: the Liam MacCarthy Cup

• The 2023 Hurling All-Ireland ran 22 April–23 July.

Format explained on Wikipedia

First, the group stages: five teams play in the Munster group, and six teams play in the Leinster group stages. Each team plays each other team in their group once.

So remember I was saying the four geographical provinces don't always correspond to the GAA provinces? That applies here. Only Ireland's 11 best county teams are in the contest, and split into 2 provinces rather than four. There are no Connacht or Ulster groups. What about the other counties? They're in lower tiers like this:

Tier 1: Munster Championship, Leinster Championship
Tier 2: Joe McDonagh Cup 
Tier 3: Christy Ring Cup 
Tier 4: Nicky Rackard Cup 
Tier 5: Lory Meagher Cup 

After the group stages, the finals. This is when everybody starts watching, it's all on telly:

 Preliminary quarter-finals (winners advance to the quarter-finals):
 * 3rd placed Munster team (five Munster teams compete)
 * 3rd placed Leinster team (six Leinster teams compete)
 * Joe McDonagh Cup champions 
 * Joe McDonagh Cup runners-up
 QUARTER-FINALS are contested between:
 * Leinster runner-up
 * Munster runner-up
 * Two preliminary quarter final winners
 SEMI-FINALS are contested between:
 * Leinster champion
 * Munster champion
 * Two quarter final winners
 AFTER THE SEMI-FINAL IS THE ALL-IRELAND FINAL

This format of finals means champions have a 2-match path to victory, runners-up have a 3-match path, 3rd-placed teams and 2nd-tier (Joe McDonagh Cup) have a 4-match path

All-Ireland Football: the Sam Maguire Cup

https://en.wikipedia.org/wiki/2023_All-Ireland_Senior_Football_Championship was 8 April – 30 July 2023

Connacht:

Has 7 teams. Six randomly play each other in three matches.

• Then the three winners plus the luckiest of the 7 play in quarter-finals.

• The two finalists both go to the All-Ireland group stage, as 1st and 2nd seeds.

Leinster:

Has 11 teams. Six randomly play each other in three matches.

• Then the three winners plus the luckiest 5 of the 11 play in quarter-finals.

• The two finalists both go to the All-Ireland group stage, as 1st and 2nd seeds.

Munster:

Has 6 teams. Four randomly play each other in 2 matches.

• Then the 2 winners plus the luckiest 2 of the 6 play in semi-finals.

• The two finalists both go to the All-Ireland group stage, as 1st and 2nd seeds.

Ulster:

Has 9 teams. Two randomly play each other.

• Then the winner plus the luckiest 7 of the 9 play in quarter-finals.

• The two finalists both go to the All-Ireland group stage, as 1st and 2nd seeds.

All-Ireland Championship:

Group stage has 16 teams = 8 described above + the winner of the Tailteann Cup, a 2nd-tier championship of teams that did not make a provincial final + 7 from the League.

These 16 form four groups of four. Each play each other once, so you play 3 matches. The winner of each group advances to the Quarter-finals and has a path of three knockout games to victory. The 2nd-places and 3rd-placed (8 teams) go to the Preliminary quarter-finals and have a four-game path to victory.

They (the governing body of the GAA) also keep changing all this, so the competitions and formats might be different if anyone's reading this comment after 2024.

Sorry for the short answer lol.