As Snowshoe Thompson said back in the 1800s, "There is no danger of getting lost in a narrow range of mountains like the Sierra, if a man has his wits about him." He had also commented that it was "unnecessary ever to remain so long in the mountains that one need be afraid of starving to death". However, the key part is the "has his wits about him" bit, as these days many people do not and thus require rescue.
Still, that's no reason not to look through a field guide, and one that comes to mind is The Laws Field Guide to the Sierra Nevada. Bushcraft is less common, in many areas the ecosystem is too delicate for such activity, and of course there's little need for it anyway.
(Pedantic note: Just as "deer" are not called "deers", the mountain range is simply the "Sierra")
The general rule of thumb is to call 1/3rd of your bodyweight a hard maximum for pack weight. At that point, the extra weight gets pretty hard on your joints (not to say I haven't seen some beastly men carrying 70+lb packs, but no one considers that situation ideal).
33lbs is on the light side. That's not a bad thing! As long as you've got your essentials, you should be all set. I'm assuming you have a stove and fuel -- there are no campfires permitted in Desolation, and frankly cooking on a fire is a huge pain in the ass. Your stove is also your emergency water supply is something happens to your filter (unlikely, but hey).
If you're on a solo trek, I suggest a novel and/or journal for the evenings. They can get lonely. If you're a curious human being, the John Muir Laws field guide to the Sierra is literally the greatest field guide I've ever encountered. I carry mine every trip into the mountains, and a pen. I write down where and when I get a positive ID on a new species of flower, bird, mammal, etc. It's a bit on the heavy side (maybe a pound?) making it a luxury for sure. Definitely not an essential for your first trip, but if you start getting curious, that's the best field guide ever.
It sounds like you're gonna do great! Have fun and be safe! If you happen to remember, report back when you get home safe! I'm going to spend the weekend wondering if I've killed a Redditor...
This is what I was recommended by a forester.
Perhaps a bit broad, but John Muir Laws' guide is great for identifying local flora https://www.amazon.com/dp/159714052X/ref=cm_sw_r_cp_apa_fabc_kLYUFb3GWGQA8
John Muir Laws' Field Guide to the Sierra Nevada <3<3<3<3<3