Hi Rincitaporfa,
I am not a staffer, but I hang around here way too often,...
You basically just payed for the extra perks of being able to upload as many drawings as you want, and to temporarily or constantly remove references from your pool, if you are a bit tired of one, or prefer to not draw from a specific one at all...
and of course for the site being able to pay their staff and for the rights to new references, that they keep adding to the site.
Hmm, advice,... looking at what you uploaded so far you aren't a total beginner. I like your shapes and clean lines, and there isn't anything jumping out which you should totally immediately do different. So, I guess best advice is... keep cruising sailor. Drawing daily definitely is good, giving critiques to other artists can maybe give you ideas what to do differently with your own art. I totally caught myself a few times explaining a beginner what to do differently, and then realized, that I heeded my own advice only sparingly, that kind of stuff.
I wish you a beautiful day and a ton of cheap art supply in grasp!