Watch this instructional video on Planche Progression and determine where you are in the progression.

The main foundation of Planche is push-ups. Essentially, you want to get very comfortable in the push-up position on the ground/dip bar/rings/paralletes and the key is to able to lean foward as much as you can in push up position. Then you transition into pike push up, essentially your vertical push strength will increase (as well as you core) significantly enough you lift your lower body then transition into a handstand. Then infinite creativity progresses with handstands.

Utilize additional resources for supplemental or beginner friendly Planche Progression exercises. The importance of scapular manipulation mentioned in the previous lesson applies to Planche (and all calisthenics movements).