Minecraft looks weird?

Why is this and how can I fix it?

It's the Java version

I have no idea what's broken there.

I would just delete the game and reinstall it. That mostly fixes the problem.

SAFE AHEAD OF YOUR WORLDS!

Have you tried reinstalling?

Reinstall.

It just looks like the assets are missing to me. So basically only layout and code is used. Fonts, textures and meshes are obviously missing. Sound probably too.

Try all of your worlds, mods, versions, … Dragging from the folder, reinstalling Minecraft and dragging things into the folder

Worlds, mods, versions, … Don't forget to save!