Scales and modes are both patterns of notes. “Scale” refers to any of these patterns, where a “mode” is a specific kind of scale.

The major scale and Ionian mode are different names for the same exact pattern. W-W-H-W-W-W-H. If you start on C on a piano, and play all the white notes, there you go. The other modes are the same pattern, but just started in a different place. Play all the white notes starting on D, and that’s the Dorian mode. Start on E, that’s the Phrygian mode, etc... They all have 7 notes, all based on that pattern.

A scale is a more general term. A scale might have seven notes (the modes, or a modified mode like the harmonic minor scale), or 5 notes (pentatonic), or 11 (chromatic), etc...

So they are very similar terms, but a mode is a particular kind of scale.