I'm pretty new to it myself, been in for about 7-8 months now. Just had my first amateur exhibition fight a few days ago. If your not too much of a runner, I'd suggest just doing 15 minutes once every day, and when you feel better, add more minutes (running is one thing I am experienced with). if you do it three times a day, you'll be prone to skipping and then you might find yourself skipping the run altogether. Once you get the running base down, you might want to do hillwork or speedwork. And with your home training, I can't offer a ton of advice since I still consider myself pretty new to boxing, but make sure you have the technique right when you do your shadowboxing and heavy bag, or you might develop some bad habits.