Well, you imply that you want to store the monster data in a database (This is done already BTW, see
https://lookupdb.guy.ht/ for someone who implemented it as a search page) but then say you want it "in plain html" the two statements are a little contradictory, plain HTML has everything the browser needs to display the page in one file, which is downloaded to the browser, typically if you want to access an external database you'll need to use a higher-level scripting language of some sort (like PHP)
So first you need to learn how to get a server and install a web server application on it, there's plenty of free/cheap webservers around use google (I used 000webhost for a free website when I wanted a place to put an example on
http://colorclock.freeiz.com/ it adds interstatial ads to your website (so on-load pop ups) but it's free)
Then you need to learn how to write HTML, I recommend w3schools, although there's plenty of other options.
If you're just looking to statically embed everything in the page (I don't recommend that, it'd make loading the page really slow and annoying) you can do all that in HTML, if you want to make the page *do* things in the browser you also need to learn javascript (again you can use w3schools for that)
If you want to pull data from a database and place it *in* the web page, you'll need to learn a scripting language, for example PHP would work and is probably the type of code that 30-40% of the internet uses for this purpose right now, although there's a lot of other options.
If you want to have the website display some data, and have it be able to *update* that data without re-loading the whole page, you'll need to use AJAX (which is actually just a specific subset of javascript, along with some server code of some sort to get the data and send it back to the client) again you can use w3schools (or your learning resource of your choice for that)