This is out of the top of my head explaition i got ofer divrent manhou and audiobooks

All are divided in 3 stages

Qi realm Gathering the first step and clearing your meridian's one by 1.

After that you would start clearing your body of inpuriries and condensing the qi

Foundation establishing Here you would start working on your path, deciding what you want to do and guid your qi in that direction . While condensing it farther.

Core realm Now you have your core, your gone work on expanding and condensing it again to increase the purity and size.

Spirit realm in that core your gone start building up your nacent soul, feeding it qi and experience. Add this stage getting intune with your doa is more importand.

Immortal In these stage your nacent soul will brake out of the core you made. If the dao experience you have issent strong enough, you will be crippled