Guide

1. Inside your Figma design canvas, click the image you wish to use as the mask and drag it above the image you wish to mask.

2. Following that, select all the layers you want to include in the mask.

3. Go to the right-side panel afterwards and then click the 'More Options' button under the Design tab.

4. Subsequently, choose 'Use as Mask' from the list of options.

5. After completing these steps, the mask effect will be applied to the selected layers.