Hari, you're close to my height. I am 193 cm. But I weigh 85kg...74kg is really thin for 191 cm! Yeah, you should put on some muscle! Eat right, eat A LOT, and work hard.
Squats - If you work out alone, you need some kind of rack - or a place you can drop the weight, or both. You can buy stands, or you can make your own using adjustable sawhorses or you can make your own out of wood. Just something to hold the bar up for you so you don't need to do a Clean and then duck under the bar. Then you can squat and drop the bar if you have to.
If you can't get a rack or drop the weights, maybe you should stick to deadlifts. Deadlifts are also very good for building muscle, and you don't have to worry about spotters or a rack. But if you can squat, do it.
Bench Press - maybe dumbbell bench presses will be better if you have no rack or spotter. You won't get trapped under the bar. Or if you can do dips, do dips and weight them when they get easy:
http://www.exrx.net/WeightExercises/Pec ... stDip.html
I know you aren't a native speaker of English. If you don't understand something I wrote, tell me and I will explain it differently. I know from learning Japanese how hard it can be sometimes.
Peter