Congrats!!!!

As to where to start, I'd say on the mountain bike, in the gym, & on the localk mountain trails with a backpack 5 days a week!
Your ost important pieces of gear will be your mind & body. The mind has to believe you can keep going & the body will have to be able to follow through...

Vance in AK.

Matthew 6:33
"But seek first the kingdom of God and His righteousness, and all these things shall be added to you."