I've tried selecting my mesh, then my armature (correct order) and hitting Ctrl+P, and selecting "With Automatic Weights", and in the content panel it moved my mesh under the armature. But it gave me an orange message with "Bone Heat Weighting: Failed to find solution for one or more bones", and the mesh didn't deform with the bones in Pose Mode.
What am I doing wrong?
(I tried to add a GIF picture, but it says the recording is too large to upload.)