DavidJ,
EQ is a tone control plugin. Like the bass and treble controls on a stereo or in your car. The primary use is to fix problems. Maybe there is too much high frequency content in your sound making it sound bright and harsh, so you can add an EQ to lower the highs to make it sound right.
One dial for treble and one for bass is very simple. Five dials or faders is more complex. 31 faders is very complex and popular with mid-range installations. Those are examples of "graphic" equalizers, giving you options but not much flexibility. A "parametric" equalizer gives you greater flexibility, but it is more complicated and takes a little longer to learn. Most audio engineers prefer parametric.
Put a song you like in FL Studio. One with lows and highs from a full band. Add an EQ and just mess with it, so you can hear what it does. When I learn a new plugin, the first thing I do to understand it is crank the settings super hard. I abuse it to know what it does. Then I dial it in for moderate settings now that I know what it does.
As for time, it depends what your goals are. Last year, I practiced mixing and creating songs about 3-4 hours a week. I was slowly improving. The year before, I was buying expensive gear and reading a lot online, but maybe only spending 3 hours a month actually working. I was improving very slowly.
This year, my goal is to quit my job to make music my job. I expect to work on it 6 hours a day. I expect to improve very quickly over the first few months.
I have two strategies for learning. Homework assignments, you might say.
1) Pick a song that you like, and that you technically have the tools and instruments to create even if you don't know how. Then try to recreate that song on your computer. It teaches you how to make sounds you didn't know how to make. I did this with Coldplay, Keane, Drake, Jhene Aiko, Pink, Lykke Li, etc. Now I know how to make a lot of different styles of music.
2) Make a whole bunch of songs yourself. Get them 80-90% perfect, then start a new one. (You'll never be able to make them truly perfect, so consider them as practice songs.) Songwriting and poetry aren't just given to some people and not others. They are skills. Skills that need to be practiced. Your first poem would suck. And your tenth. Maybe your 30th is okay, your 80th is pretty good, and your 200th poem is super good. Songs are the same way. Just make more and more and more music and you will get better.
Spend 80% of your time making music, and only 20% looking for help and tutorials to learn to make better music. If you need to buy gear or instruments, do your research. But gear doesn't make a popular song. So buy the gear you need, then go back to 80/20.