Poker How do you study poker to improve your skill?

I am at a crossroads in playing poker and don't know where to turn. I need to learn to put my opponents on hands although i can do it somewhat at different times, I need to improve at it. I need to learn what my range is and what range will be best for me. I need to learn more, but I just don't know how to learn this without someone telling me how to study poker. So i am asking you guys how do you study poker. What do you do? Is going over your hands with flopzilla good to do? is it all you really need. How can I get better? what do i need to do? share with me what you do to study poker so I may come up with a Plan that will work for me.
Thanks

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