Sure, here is a 3-day dumbbell workout plan with a focus on different muscle groups each day:

Day 1: Chest and Triceps

Warm up: 5-10 minutes of light cardio (e.g. jogging in place, jumping jacks)
Dumbbell bench press: 3 sets of 8-12 reps
Dumbbell flyes: 3 sets of 10-15 reps
Dumbbell tricep extensions: 3 sets of 10-15 reps
Close-grip dumbbell bench press: 3 sets of 8-12 reps
Overhead dumbbell tricep extensions: 3 sets of 10-15 reps
Rest for 1-2 minutes between sets.
Day 2: Back and Biceps

Warm up: 5-10 minutes of light cardio (e.g. jogging in place, jumping jacks)
Dumbbell bent-over rows: 3 sets of 8-12 reps
Single-arm dumbbell rows: 3 sets of 10-15 reps
Dumbbell bicep curls: 3 sets of 10-15 reps
Concentration curls: 3 sets of 10-15 reps
Hammer curls: 3 sets of 10-15 reps
Rest for 1-2 minutes between sets.
Day 3: Legs and Shoulders

Warm up: 5-10 minutes of light cardio (e.g. jogging in place, jumping jacks)
Dumbbell squats: 3 sets of 8-12 reps
Lunges: 3 sets of 10-15 reps (each leg)
Dumbbell shoulder press: 3 sets of 8-12 reps
Lateral raises: 3 sets of 10-15 reps
Front raises: 3 sets of 10-15 reps
Rest for 1-2 minutes between sets.
Remember to warm up before each workout and stretch afterwards. Also, make sure to use a weight that challenges you but allows you to maintain proper form. As you progress, gradually increase the weight to continue to challenge yourself.

As for project ideas, you could create a before-and-after fitness progress tracker, where you log your weight, measurements, and photos each week to track your progress. Alternatively, you could create a home workout video series and share it with friends and family. Good luck with your fitness journey!
spam fails_task lang_mismatch pii not_appropriate hate_speech sexual_content quality toxicity humor helpfulness creativity violence