O nae yar...
it is totally wrong to say that gym is for strong body person, im underweight (even after 6~7 months of gym an year ago and having good diet).
You get strength through exercise, gradually you built up your muscles and lifting weight is also increased. I got about 6kg body weight increased in about 3~4 months then it was stopped for next few months and there was quite a difference of weight which I used to lift in starting days to what I was lifting in the ending days. And I am sure that had I been continued to gym, I would definitely have gain more kgs.
Regarding type of exercise, watch tutorials on youtube or go to gym have a training for a month or two from there, or make any friend there who is experienced, then you will be on the go.
and regarding your tough routine, I believe that if someone keeps good diet all the day, juices, good food, good sleep then you can daily go to gym. BUT you MUST have to take good diet after the gym as well. Otherwise such hectic routine will have a -ve impact on your body.
Remember, Good diet along with Good sleeping hours and a proper exercise will lead you towards betterment.
and once you start the gym, you will be so habitual that "kabi chuti krny ko dil nae karay ga" , just have a niyat....dont be a sust person...
cheers.