So I was trying to get Ubuntu to be able to change the screen brightness correctly, and in one of the forum posts, someone suggested to try to change the grub file with "nomodeset." After I did so, my Ubuntu boots up to a full purple screen and gets stuck there.

I pretty much need to be able to modify my grub file again and change it to what it originally was. How can I do that?

Help please?

EDIT:

I tried booting into recovery mode, but I can't get past the black screen with all the text written on it. I think I'm getting a udevd error related to my graphics card.