Credits to original owner of video. For educational purposes only.
Tools used:
Adobe After Effects
CapCut
Procedure
Step 1: Import & Duplicate
1. Import your raw video into After Effects
2. Drag it to the timeline
3. Duplicate it 5 times (Ctrl+D)
4. Rename each layer: hair, skin, shirt, pants, shoes
Step 2: Roto Brush Each Layer
1. Double-click a layer to open in Layer panel
2. Press Alt+W to activate Roto Brush
3. Paint green strokes on that body part only
4. Paint red strokes on everything else
5. Press play ▶ to propagate all frames
6. Click Freeze in Effect Controls when done
7. Repeat for all 5 layers
Step 3: Apply Fill Colors
1. Select a layer
2. Go to Effect > Generate > Fill
3. Repeat for all 5 layers
Step 4: Add Green Screen Background
1. Go to Layer > New > Solid
2. Pick green color
3. Drag it to the bottom of the timeline
Step 5: Export
1. Press Ctrl+M to open Render Queue
2. Set format and output location
3. Click Render