Screen freezes

A few days ago, I started playing a Minecraft map in 1.20.1. The map in question is "Ragecraft IV", and while it is vanilla, it does make use of a heavy datapack for mechanics, and a resource pack for music and textures.

The problem is that, every now and then, his game will crash and his screen will freeze. Once this happens, he'll be able to move around, but his video will be entirely frozen. His current PC is a Lenovo Thinkcentre m90n-1 11ad nano , and is using a miniOS called Windows-X Lite.

Things we've tried so far:

• Allocating more RAM to Minecraft.

• Running the game with both Sodium and Optifine.

• Reinstalling drivers.

• Lowering video settings.

• Installing a new Java version.

• Getting the system better cooling (apparently, this happens even when it's cold).

• Launching the game through MultiMC.

There may be some methods I've forgotten, but that's it off the top of my head. I really need help with this, as I bought him this PC so we could play this map.