my minecrfat java edition launcher does not work

when i start the launcher it just says that i have run into a bug an that i should get help here and another thing different from the launcher, last when i played minecraft i could not join any servers and when i tried to join a server like hypixel it just sed "not athenticated with minecraft.net" pls help me with the server thing and i have tried to uninstall the game and reinstall it but its then when i ran into the bug i have only bought minecraft a few weeks ago