so, what happens is i start a world then the colors and game show up for a sec and then it degrades into colors ranging from green to a dark gray, anyone have any ideas how to fix it? already reinstalled the modpack and updated java and made a new world

We get this every once in a while. It is usually solved by making sure you have all of your computer's drivers are fully up-to-date.

if my drivers are up to date?

Please update your drivers to the latest versions available, restart your computer and try again.

#203 (comment)
it's a common bug for intel drivers and really old game versions