Complete these steps in reverse from here to reassemble the components after the disassembly:

Insert RAM, M.2 SSD and any other components you removed before moving forward.

Lastly insert the battery being careful once it is disconnected not to use any metal tools and avoid electric shocks and shorts etc.

Carefully reattach the bottom panel of the case to the laptop body, snapping the contact points back into place and screwing the case screws in.

Carefully stick the rubber feet/strips back down and power the device back up.

Power the device back up and it should work as normal.

This should complete a basic breakdown for troubleshooting common issues but more detailed tear-downs with further steps are available online...