The “best” grip for you depends on the size/shape of the mouse and your hand along with your personal preferences (whatever is more comfortable). You should try a lot of different mice in a shop. Trying to copy someone else’s grip is probably a bad idea.
I have fingertip grip. (Requires smaller mouse than claw and palm grip.)
I hold the mouse with thumb and little finger on the two sides of the mouse.
(Requires a mouse with suitable curves on the left and right sides.)
Pointing, middle and ring finger are always on the 3 buttons (left, scroll/middle, right).
Always used this grip. It feels natural. Putting my pointing and middle fingers on the left and right buttons would require too wide/uncomfortable stretch between those two fingers.