Which hardware I need?

Hello Everyone,

I am totally new here. I hope i am asking the question on right place.

PX4 Latest Stable Release V1.10.1 has Autonomy Stack which can be used for localization ( i suppose without GPS ) and obstacle avoidance. My question is which hardware I need to have on drone to provide inputs for the stack. How can i know details about this ? I mean the detail for implementation and how the stack works ?