How ? Well pretty easy.
Get a bar and weights up to something like 150 kg. Then you can do deadlifts, curls and stuff like that.
Use the floor for push ups, sit ups and more. Use weights for that as well.
Then you just need motivation and you can get both big and strong at home ;)
I WORKOUT AT HOME,I HAVE 275 IN FREE WEIGHTS 60LBS DOWN TO 15LBS IN DUMBELL SETS ..WEIGHT BENCH.LAT PULL DOWN MACHINE AND A POWER TOWER,THAT PRETTY MUCH GIVES ME EVERYTHING I NEED.YES ITS VERY EXPENSIVE BUT WORTH IT ON THE LONG RUN IF YOUR TRULY COMMITTED TO WORKING OUT FOR THE LONG TERM,IF NOT JUST GET A MONTH TO MONTH GYM MEMBERSHIP
You can do a little bit of Google research and find some really good bodyweight strength routines.
You don't need to have all the money for a home weight set to build muscle. All you really need imo is a pullup bar (ideally variable height for also doing inverted rows) and a dip station (parallel bars). You can get them for home relatively cheap, or you can often find both of these somewhere in your community. Some elastic resistance bands might be useful. Eventually you might get to the point where you need to add a weight belt or vest to make those exercises more challenging (I just used a backpack with weight in it).
Basic foundational exercises:
Pullups, dips (do research on proper dip form as they are injury prone otherwise), inverted rows, pushups (various styles)
Squats (various), pistol squats, lunges
Google the phrase "bodyweight alternative Deadlift." for some good ideas also.
You can do almost anything for cardio, jumprope is a good one.
You can really build an awesome, scientifically maximized routine out of just those exercises.
If you eventually got a basic adjustable dumbbell set you'd expand your potential by a lot.
Eventually, with more money, you can add stuff like an adjustable Bench, then an Olympic bar and weights, and a squat rack, and you'd have a great home gym.
A very simple way to start is to buy a multi function bench . Get a bench that can detach from the stand that inclines and declines. Then a barbell stand (cage or uprights), Olympic bar or standard bar and a 110 pound set of plates and collars. A few fixed dumb bells. Keep in mind an Olympic Bar weighs 45 pounds. So if you can afford a little more in plates go for 300 . Make sure the bench is rated for your weight plus the weights. Other equipment like curl bars , ropes etc. are great to add to a gym over time. If you are social or like to train with a partner, I would keep your home gym basic and invest in a membership in a gym that has all the equipment geared to bodybuilding.