: hello.

The simplest method is: (in any input method state)

Root sign √: press the shift key (Alt) with your left hand, press 4 1420 with your right hand in turn, and release the root sign √ with both hands to come out.

Square? : The left hand is the same as above, and the right hand presses 178, superscript? Came out.

Cube? : Same as above, press 179 with the right hand in turn, superscript? I'm out.

Please try it. Good luck, goodbye.