What should I plan for?
What should I pack?
Which is the best one for me?

The answers to many questions here are...It depends.

Planning and prep are highly dependent on a variety of factors;
What is your state of health? Where are you located? What is your budget?
Season? Altitude? training? Others in your primary group?

Etc. and so on on.

We're here to help, but often the answers is -- well, this is what worked well for me. YMMV