For those who monitored questions in this site, I read this one: Rigging character, mesh not following bones I doesnt solve my problem. Many similar question posted on the internet doesnt solve the problem.
I cant rig my character here, I followed the tutorial from the official blender channel in here https://www.youtube.com/watch?v=cZ3o5tjO51s&list=PLa1F2ddGya_-UvuAqHAksYnB0qL9yWDO6&index=30
I did exactly what he did, go to object, select mesh, select armature, ctrl p, with automatic weight
in pose mode, the mesh wont follow the bones
Also edit mode is sometimes inaccessible, for some reason