Common Chord Progressions
Practice E-shape chord progressions that are used in many songs.
Some chord progressions are used in so many songs that it's worth practicing them on their own, for reuse in many other songs later. First practice making the chord changes. Then practice various scale patterns over the changes, and come up with melodies that sound good linking one chord to the next. This practice carves channels into our nervous system that we can reuse to improvise fluently over real songs in the future.
I-IV-V with perfect cadence
The common "three chord song" progression, tagged at the end with a perfect cadence.
Pop progression
The famous four chord progression used in hundreds of pop songs.
50s progression
Common in American pop songs in the 1950s.