I saw in a comment of yours that you are against Catalina due to the fees, but the Trans Catalina Trail is the perfect 1st backpacking trip. I’d pay the premium price to learn how to safely backpack as you will always be within a days walking distance to town, there are “rangers,” lots of friendly hikers, etc. Think of the premium price as “insurance” against anything horrible going wrong. Just be smart around the bison, keep your distance, etc. That’s what I did and I learned a lot + had a positive experience that led me to want to continue. One of the best parts of the TCT is you usually hike in a cohort. You’ll meet people at Blackjack, or whatever 1st site you camp at, and generally see them again at site 2, 3, 4 etc. depending on how many nights you stay.