Every time I try to enter my world it usually doesn't even get to the loading screen animation without hanging. 2hrs of waiting and I didn't see any improvement/progress.
If I click on the window while its loading even after I just clicked start it'll say its not responding

my laptop is nearing the end of its life and I usually point my stand-up fan at it to help keep it cool
but it can still run Minecraft on normal graphics at 40fps (which is good enough for me)

but just 3 days ago I could easily open my world after like 1 minute which isn't bad seeing how many mods are in this mod-pack