HOW TO ADD GIFS : MASKING
MASKING GIFS : TRANSPARENT GIFS : BG GIFS
O1. Go to your graphic and click on the Share button > PSD (Preserved Layers). It'll be in layers then flattened.
Now go to the Magic tool > Layers Icon (Right side bar) > Go to the layer you covered to be masked.
Click on it and it should give you a selection tool. Click Folder > Mask and it should show up like that!
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You know what to do! Photopea with your gif! Open Computer > Photo Library.
Layer > Duplicate Into > Graphic
Now, drag your gif to the folder + mask and insert it inside via holding down and dragging. It should be perfect.
Result