Hello there.
It’s great that you’ve decided to build yourself on the theoretical aspect of web development first instead of just trying to jump right into this field. But as even you must have felt it that doing just this isn’t enough so, the first thing would be to not to build a “bunch” of sample sites.
Instead get all your ideas together, give yourself some time to organize for a proper project and then give it your best shot. Because this is something that’ll be something like a portfolio. Such projects are given some serious consideration, so put some time and effort into it.
Or a different thing could be is that you could work and get proper certifications from Oracle for MySQL for example if you think you can study for these exams on your own that’s great or you can get trained. The best advice can come from your trainers because they’ll be able to gauge your skills and interest in the field.