Here's how to get Kabuto and evolve it:
1. Find Kabuto: Kabuto can be found in the Fossil Restoration Center in Cinnabar Island. You need to find a Dome Fossil first.
2. Get the Dome Fossil: The Dome Fossil can be found in a hidden cave in Route 12. You can get access to this cave after defeating the gym leader in Lavender Town.
3. Go to the Fossil Restoration Center: Go to the Fossil Restoration Center, which is located at the top of Cinnabar Island.
4. Revive the Fossil: Speak to the scientist and give him the Dome Fossil. He'll revive Kabuto for you.
5. Level Kabuto up: Level Kabuto up to level 40 to evolve it into Kabutops.
Remember: You can only get one Dome Fossil per game, so you can only evolve one Kabuto into Kabutops.