I would be much more likely to use a service that is referred on Facebook for a one man show like this.
Using Wordpress here is the wrong choice. You will need to harden it. You will need to maintain it. You will most likely get hacked, and your trust will be destroyed.
Taking photos on your...
That will give you a gradle or maven project that is ready to run containing a single controller/endpoint
Also - https://spring.io/guides/gs/spring-boot/ & https://www.baeldung.com/