Just bought an exercise bike, where you follow trainers through an app..is it safe for me to just dig in to the exercises at age 58, i have never really done much exercise before, so should i be concerned?

Hard to say: With no background information on your past or current medical history, exam & possibly tests it is hard to give a blanket approval for an exercise routine. You could be a heart attack or stroke ready to happen during any such endeavor. It would be a good idea to contact the doc who knows your status to gain guidance on this effort.

Agree with Dr. F: It would be prudent to get clearance from your doctor. In any case start slow with low intensity exercise and gradually increase the time and intensity as tolerated. Have a healthy diet, exercise 30 minutes/day, drink plenty of water, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/. Wish you good health!