Hey @nschlueter,
Rather than reading a chord chart, I’d suggest just learning three or four closed chord shapes and the theory to be able to apply them anywhere. This way, you won’t end up dependent on a chord chart. Once you learn a closed chord, you can move it anywhere you want on the neck. For instance, take 2245, an A chord shape which is the basic open G chord moved up two frets and barred. If you want to play a Bb chord, just move the whole shape up a fret- 3356. Need to play a B minor? You can take that same shape, knowing that flatting the 3rd tone makes a minor chord, and play 4457 for a B minor. Same ideas for something like an E chord- just take the open D chord and move it up two frets.
This collection of lessons is a great comprehensive study on basic mandolin rhythm:
https://banjobenclark.com/courses/basic-mandolin-rhythm?from_track=beginner-mandolin-checklist
This lesson as well:
https://banjobenclark.com/lessons/nick-dumas-rhythm-chop-techniques-mandolin-intermediate