Where is the best 3D game engine free and easy to learn?
Easiest I assume coppercube, since you don’t need to learn a coding language.
Best performance for very old pc’s / laptop is panda 3d / ursina
Well documented with nearly unlimited tutorials and help from the community is unity.
Fully free and open source is godot, tho not very mature yet.
But these answers you got already multiple times.
I would have thought Google is more appropriate for your question rather than asking on a 2D specific site for GDevelop. This is just laziness. Shame.