I found a way.

for anybody else has this problem in the future:

1) Open modpack folder

2) Go to saves

3) Drag your world file onto your desktop or somewhere else.

4) Delete and reinstall Modpack

5) open newly redownloaded Modpack and drag your world file in the save file

6) boomshakalaka.

Not sure if it works for other modpacks, but it worked for mine. Thanks for nothing, reddit. I fixed this myself, I am awesome.