Fix error message in Java (Minecraft)?

I have one or two problems; I have uninstalled Discord, and now I can no longer install it because it says that Discord is still open somewhere else. I also think I know where (now we come to my title) with Java or Minecraft. I've played Minecraft many times and Discord somehow connected to it. In short there's now an error message: JavaScript error occurred in the main process bla bla bla, I have shut down my laptop many times but the error message "Ploppt" keeps coming up. Can anyone help me? Have already googled but there are complicated terms I know not what it all means. Thank you in advance.

Something may have gone wrong during installation because Discord can't find a module.

I can help you with Discord.

There are still remains of Discord in different folders.

If you enter the key combination Windows + r and then enter% appdata%, there will be a Discord folder there. You have to delete it. You have to do the same thing again, but enter% localappdata%.

Okay and how do I fix that please?

Yes with localappdata this error is shown to me (so that it is not open yet) so it doesn't work: //