Pan – left mouse button while holding 1 key, or center mouse button while holding ALT/OPT key
Dolly – left mouse button while holding 2 key, or right mouse button while holding ALT/OPT key, or scroll wheel
Orbit – left mouse button while holding 3 key, or left mouse button while holding ALT/OPT key
Bank – Right mouse button while holding 3 key
Some people prefer to keep their keyboard hand over the 1-2-3 keys and always use left mouse button, while some prefer to switch fingers on the mouse from left-center-right buttons while keyboard hand is ready on the ALT/OPT key (assuming you have a three button mouse). I learned the latter first, so that’s what I tend to stick with. Go with whatever floats your boat. Hope this helps.