Is it possible for traveling in West Coast in USA without a car

I am planning a 15-day travel itinerary, starting with a landing in Los Angeles.I want to go to Los Angeles, Las Vegas, San Francisco, and Yosemite.But my driving skills are not very good, and I am not very familiar with the rules of driving in the United States. Can I travel there without a car?For these places, what would be a reasonable route?