Why do I often time out?

Whenever I play online (Overwatch, Fortnite) I have a request timed out every few seconds. I'm connected via lan and have already tried a lot, but so far nothing has helped (Rooter restarten brings nothing). While playing, my ping is actually good (10-20). Does anyone know how I can fix this?

Try to finish all programs and processes that are not necessary for the game.

Windows 10 instead of xp please

What about other online games?

Probably formulated my question ungünsitg, these ZEITüberschreitungen are also available without games. So they are always there