Is this an external mouse or the internal touchpad?
1
If this is the internal touchpad, on your keyboard on the function keys (F1 - F12) does one of the keys have a symbol representing a touchpad with a line through it?
If so, try pressing that key or Fn + that key to test if that gets the touchpad working.
2
If not, right click your Start Button and open Device Manager, then expand the 'Mouse and other pointing devices' section.
Please provide a screenshot of that full window.