The town of Bishop would be your base, and you can get there with public transportation from the airport in Reno, NV. Good stores if you need to replace equipment.
The roads to the trailheads are paved - a normal passenger car can handle the roads. Only about an hour from Bishop. There are commercial shuttles too. Even hitchhiking (I've done it, and I'm an ugly old man, and still had no trouble getting rides). The parking lots are already at high altitude, about 10,000 feet, so you only have to go another 2,000 to get over the passes.
The actual trails are in good shape, good surfaces, not narrow, not scary. There are places to camp both before and after the highest point of the passes so you can hike at your own pace. If you wanted to camp at the trailhead the night before to get adjusted to the altitude, then go just, say, just 5 miles and 1200 feet your first day, you could do that, and the trails are beautiful the whole way.