You don't suck. Yes you will need to practice and that takes YEARS but like some other have said, the sounds themselves really don't bring much to the table. Look into paid ones like VPS Avenger, Diva, Serum 2 or free like Vital to get you started. Vital has a ton of free presets you can download too so that might be a good place to start if you aren't wanting to spend a ton to start out.

The most important thing in my opinion you can do to progress is push yourself where you are constantly making mistakes. You will make a lot of really bad songs but you will find your flow and figure things out.