help.I can't join any modded servers

When I try to log in to any server that has mods, an inscription appears on my screen (see attached screenshot).I know a way, you need to download mods manually, but this is not a solution to the problem. I had this problem a long time ago, a year ago when I was playing the same thing.I tried to reinstall the game, check the integrity of the game files. I honestly don't know what to do.