If you want to go far in the hip hop industry, you will need high quality rap instrumentals. I'm not trying to downplay the importance of lyrics, but without an instrumental, nobody will want to listen to your music. You could of course rap a capella only, but there are few people who listen to a capella only.
I mean, think what it would have been like if Tupac rapped only a capella. You probably wouldn't have even heard of him. Now think of what it would have been if he didn't get production from Shock G, Dr. Dre and Johnny J. Tupac wouldn't have been as widely known as he is now. I think you are now beginning to understand the importance of the instrumental in rap music. The instrumental usually sets the mood for the entire song. Without it, your lyrics probably won't have the same impact. And if you don't have an impact on your listeners you won't be remembered.
While Tupac is a very talented rapper, and some even regard him as the best ever, his success is also due to the high quality production that backed him up. Now, if you take some of the beats that Tupac rapped on, it would be really hard to make a bad song with them, even if you put a bad rapper on them. In Tupac's particular case, his lyrics and the beats usually were in perfect harmony.
You will need an instrumental that matches the subject of your lyrics, no matter what are you rapping about. As a matter of fact, this is the most important thing you should look for when you look for beats to rap to, whether your lyrics fit the beat, or the beat fits the lyrics. I mean, think of what would have been if Tupac rapped "Only God Can Judge Me" to an instrumental like Lil Wayne's "Lollipop". The instrumental just doesn't fit the subject of Tupac's lyrics.
So you need to find your own style of beats. When it comes to selecting beats, you can get your inspiration from other artists. Look at what they rap about over what type of beat and what elements does that beat have. If you are making party songs, you should look for rap beats with a fast tempo and a synthesizer-based sound. If you make socially conscious lyrics you should look for beats with soul and jazz samples or beats with guitars and piano. I'm not saying that you should limit yourself just to that, I'm merely giving you some guidelines.
With the fitting instrumental, you song could turn out to be a hit, or even turn out to be one of those timeless songs, that you never get tired of hearing.
No matter the outcome, you need to work a lot to get somewhere in the hip hop music industry. You need to invest time and money into beats, recording, promotion, marketing etc. Without that, you will never get anywhere in the rap game.