Patagonien (Chile) Hiking

Hey i gonna stay in Chile from Oktober 26. Will arrive in Santiago and wanna make my way all the way down to the south. I'm really into Hiking and wanna explore Patagonia as well.
Now the questions:
I read a lot about reservations and Guide Tours.
Is there a chance to have a good time without reservations in the future. I have to no idea when I will be where. Will look for some hiking buddies as well in this time.
Are there any Tipps or recommendations to stay spontaneous kind of?
Are there hostels etc around this area? Like around torres del paine?

I will bring tent etc with me and I'm open to use it.
Are the also to find any spontaneous guided tours or am I kind of delusional?

Thanks and hope you all do great!