Another Noob question

I know there will be an obvious answer to this but i’ve looked through the tutorials and i’ve searched the forums and I still can’t find an answer. I’m new to Blender and 3D modelling n general. I picked up Blender because I needed to do some mechanical objects for a friend and here’s the problem. I have the objects modelled, textured, coloured and animated. The problem I now have is that I need to cut some holes through the objects (screw holes/pin holes). Is there an easy way to do this please?

there used to be, but that code is not supported anymore. But you can try the Boolean tools (search for that very non-obvious term)

the easiest way I know of is to add a plane. In face mode, delete just the face. in edit mode, add a circle. Then with all the verts selected, hit F or shift F to beauty fill in the faces. Then delete the faces inside the circle, and extrude that.