>>2269062>Go to /fit//fit/ has some decent advice, but most of them are poor kinesiologists and poorer dieticians. I wouldn't listen to their diet advice.
But if general health and physical ability is your concern:
Let's say you want to run farther, do more pushups, etc. First piece of advice is this, don't get bogged down in metrics, in fact, as a beginner you can ignore them, aside from your maximums.
Make time in the day to add your exercise frequently. You will want to do your chosen exercise few hours or so, but less frequently is fine to start.
For an exercise that is based on lifting weight, do less than half your maximum. For running, you'll want to run until you feel warmed up. These metrics seem unhelpful, but what you're looking for is this: You want to feel that you've woke up your muscles but not feel fatigued. You shouldn't feel exhausted, overly sweaty, or gasping for air. You should feel pumped up like you're ready to go again.
What it looked like for me was three pull ups (max six), jogging for four minutes (max eight), and ten pushups (max twenty), every two hours. I did this for three weeks, two days on and one day off (schedule looked like Mon-Tue on, Wed off, Thu-Fri on, Sat off, etc). Afterwards, I had improved my maxes to twelve pull ups, fourteen minutes jogging, and twenty-eight push ups. Improvements thereafter slowed, so I changed to a more intensive exercise regime and started to specialize the routine for exercises that interested me.
However, the point is that consistent repetition, without damaging the body, builds a your base ability. If you concentrate too much on results like "run for 15 minutes," you will disappoint yourself as a beginner. Identify your maximums, and work within them consistently. This is the same as any skill. Musicians, linguists, mathematicians, etc, all build on foundational skills. Walk before you run, etc.
Also, ignore the advice of anyone who doesn't include rest days. They're universally idiots.
