All about permits for newcomers

I am a backpacker who likes hiking, bushwhacking, and dispersed camping. I am from San Diego and like to find places up to 3 hours' drive. It is very confusing and time-consuming to check every single trail and area to see if they required a permit for parking, dispersed camping, or even hiking. Most of the time I am not able to schedule my hikes in advance. In other states, I go bushwhacking, and whenever I feel like it just camp somewhere and the next day continues my hiking without any permit. That's the way they are. It is very hard and almost impossible for me to schedule weeks ahead and decide which area or trails I wanna hike and where and for how many nights I wanna camp. From my understanding, in most places in California, we can't dispersed camping, and those places that let you do that require a permit with snail mail and we need to let them know where to start and finish and how many days we want to hike. My question is, is there any way or any area that I can be free to go for bushwhacking and camping without a permit or getting some kind of yearly permit or something? I appreciate yout time and help.