High Sierra Topix

I am new to High Sierra hiking and I am planning to hike on the John Muir trail from Tioga Road to the Sunrise huts. And then to the May Lake the next day. I would like to talk to someone who has experience on these trails. I have questions about what the trails are like, and level of severity of the hike.

First of all, welcome to HST !
The trip you mention covers some popular trails and, as such, the trails are "well worn". You won't have any trouble finding your way. They tend to be somewhat sandy and dusty, especially in the summer. Water is generally available, but check a map for sources.
Level of difficulity ? That depends on your level of conditioning. IIRC, Sunrise is in the 9500-10000 ft evelation range, as is May Lake. Some people start to experience altitude sickness at those elevations. I would suggest you spend a few days at Tuolumne Meadows to get acclimatied before you start your hike. You might also want to take a few day hikes out of the Tuolumne Meadows area to "test" your conditioning before commiting to a two or three night trip. Start at Tioga pass and either hike up Mt. Dana, or go to Gaylor Lakes across the road for day hikes.