You need to provide way more information, but to point you in the right direction:
First you need to make a KinematicBody3D as a “Player controller” and then you just add the 3D model as a child of that.
Probably you should first download the model and then look at that. The models don’t have any texture but there skin is present as .png image. They don’t have bones but bones are available as .fbx (another format) what I need to do is combine all these. but not getting how!