If your trying to find what workouts to do I would look up doing a push pull legs split. There are a tone of videos online regarding this split and it really helped me starting out

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20-30 minutes is more than enough time for a good workout. It would be good to do a split (where you divide you workouts into seperate body parts per day) for example push, pull, legs where one focuses on pushing muscles (triceps, chest), pulling muscles (biceps, back), and legs. Or upper, lower split. You could do full body 3x a week with 3-4 exercises focusing on different muscle groups with 3-4 sets each exercise. You got this!

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