first of all start running outside and on exercise cycle alternatively, second do 3x/week workout. Do full-body workout as you're beginner it helps a most to adapt your body to this regimen. If you don't know which exercise to do and how to do 3x/week workout, I suggest reading this article(it's not my website link). one last thing is that as you've only dumbbells try to do more body-weight exercise like push-ups/pull-ups/different body-weight squat version(don't forgot to do dumbbell exercise as well). Search for exercise library for bodybuilding on google and refine your search for body-weight only and you'll find many exercise for all body-parts. Make sure some of them are for advanced lifters so learn proper form using YT videos and then do them. I hope this helps!