Sending marketing text messages without explicit permission is a violation of the CAN-SPAM Act in the USA, and I’d imagine the EU probably has similar rules. You could rack up some pretty hefty fines if you continue to do that and someone decided to report you. Emails and phone calls are the way to go.

Also, as others have pointed out, you need to polish your skills (as well as your website) before anyone is going to take you seriously. Websites are easy to make with sites like Squarespace and Wix, and a (real) professional website doesn’t cost that much from someone who’s actually educated in web design/programming/whatever.

I applaud your eagerness and enthusiasm and I encourage you to keep it up but you’ve still got a ways to go. Maybe take your self taught knowledge and enroll in a course at your local community college or something.