How should I go about building a website with a Java backend accompanied with a database [on hold]

Apologies for the vague question title, it was difficult to come up with something short enough!

In my final year at university I made a Java application that did some manipulation of data from several APIs, and then stored this in a database. I then had a simple website that would present this data in graphs etc. It's worth noting that I ran all of this locally, and the amount of data stored will end up being fairly large. The reason I'm using Java is that I need access to a library that allows me to do the data manipulation that I need.

What I want to know is, how would I go about setting this up as a fully hosted application? The Java app needs to collect data every 30 minutes. I'm assuming that I could create a REST API that the website can then access?

I'm fairly new to web development, so sorry if I've got some of my facts wrong. I'd appreciate any help in terms of the direction I need to go in. Thanks! :)