First things first: you need to know the basic anatomy of the human body i.e. the names of our musculature. The below is courtesy of bodyweightexexercise.blogspot.com and provides a good basic overview of what muscles are located where, and what we call them. Yep, you may well know all this. Then and again, you may not. Regardless, I would be doing a disservice by not pointing these out. It's a lot easier matching exercises to body parts when you actually know what body part said exercise is for.
While we're at it, I'm going to make a wild assumption that you know where the neck and forearms are seems as they're not labelled on the above image. Aroha mai if I sound condescending (but I confess it does feel strangely good being an asshole sometimes!). But enough of that. Now that we can see what is where -- and what it's called -- we can visit the Exercise basics link to examine what exercises best hit each of the above areas most effectively.
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