I made a first person shooter game in godot and currently I have a bad looking weapon for my character. I made a new pistol in blender, I exported it as a .glb file and I tried to replace the gun from the MeshInstance Node but I gave me an error: "The selected resource (PackedScene) does not match any type expected for this property (Mesh)." Any solutions please?
The error is telling you that you are trying to assign a Scene to a Mesh. Those aren't the same kind of thing. Scenes have nodes, some of which are MeshInstances, some are other things (lights, colliders, etc...).
You have two options: