I’m doing Spaceship Shooter tutorial and I would like to change the way I control the spaceship from the keyboard (WASD or arrow keys) to moving player using the mouse. how I do that?? pls help

First, you will need to completelly remove the inputs in your Project’s settings. You can do that by going in: EDIT>PROJECT SETTINGS> INPUT

You can either delete all the inputs or leave all the keys as blank, you choose. An alternative would be to just remove the control by keyboard in your character controller. Then you just need to make a script that uses the mouse to control the player.