I forget where i found the source, but the Cdc estimate that every 1 in 5 cases results in long covid. A survey of 100k cases found 26000 people are still having symptoms after over month: https://www.sfgate.com/bayarea/article/Study-reveals-long-COVID-risks-17200501.php?IPID=SFGate-HP-CP-Spotlight

For the UK they think 2 million have long covid: https://www.theguardian.com/world/2022/jun/01/two-million-people-in-uk-living-with-long-covid-say-studies