Do some ghetto workout shit.
As in, use a playground when no one's around and do dips, pull-ups, chin-ups, hanging leg raises (great for abs), incline/decline push-ups, crunches, abs. For cardio, sprinting, running, parkour style movements (assuming you can get enough room for them) is enough. Hell, if you can find the space, do cover-to-cover type movements if you're so inclined.
Eat something that's got some fiber, protein, vitamins, and carbs to help fuel muscle growth (eg. chicken, jasmine rice and spinach) and you'll be making them gains in no time!
Eat small meals throughout the day that'll keep you filled up instead of big meals at intervals. It's better and the hunger won't be as much of a ***** to deal with.
But most importantly: do you. Do what works for you.
Then again, my perspective is one of someone who looks like an offensive lineman, so take my hints with pounds of salt and cocaine.
If you want some better advice, I'd recommend Hodge Twins, Barthelfitness, and Scooby1961 on YouTube.