Are there any fitness people here? gots some questions about lifting

Kay. so I've heard a few times I'm just some muscle away from being very attractive, and that's what I Want.

First of all, if I really worked at it how long would it take to get some definition? I'm currently in the 140lb range and am about 14% body fat.

Another thing, I always hear lifting free weights is always so great, not knocking it at all but what I wanna know is if it really is a great way to improve physique, why do these p90x and insanity workouts (or the ones that encourage using body weights) claim to yield great results in a short time? I know its TV and may be fabricated but still. Do these workouts create "useless" muscle and mainly is just for definition?

If I'm already pretty weak atm (I could curl 25lb dumbbells 10 times fairly easily but 2nd set was difficult) what would be the best way to go about it?

Also, are weight added pushups an effective workout? When I was doing them regularly I could do 20~ or so with 50lbs added easily. Didn't try much passed that though because I only have a backpack and the weights started to hurt my back.
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Also I'm 5'7
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+1 y
I had my weight wrong, I'm 150 lbs roughly 15.5% BF
Are there any fitness people here? gots some questions about lifting
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