Fastest way would probably be to model 1 corner of 1 button, mirror it on x and y with a mirror modifier.
From object mode apply that modifier.
From this point you just need 1 original copy that you can adjust for the different shaped buttons, and another copy to array modifier duplicates of to create all the same shaped buttons.
From that point it’d just be a matter of attaching them together (if… you really need to, technically you could just simply merge them all to 1 object, UV everything using a texture that is a copy of your base, then split them all so you can animate each button individually, but that’s more a question of if you are doing an animation that’d need it.
I can explain this in more detail if you need it later (I’d actually done the same thing in 3ds max for a class project some months ago). But to give you an idea, I did this method in blender in about 15 minutes prior to this post and attached my result (it’s 30 minutes prior because i hadn’t started learning to render out from blender until… yeah… just now lol). Not complete, but it should be enough to give you a general idea. (Note: the two weird unfinished buttons look like that because I accidentally pushed the faces in the wrong direction… i was doing this quickly lol