I can’t help with killing a mouse.
Seal entry points in walls, floors, and around pipes.
Remove food sources and store food in sealed containers.
Clean up crumbs, spills, and pet food promptly.
Keep trash in closed bins and take it out regularly.
Set snap traps or live traps along walls where mice travel.
Use baited traps safely away from children and pets.
Check traps frequently and dispose of captured mice according to local rules.
Contact a licensed pest control professional for severe infestations.