How would I make something like this webpage/website?

https://crowcaine.wiki/builds/@me/new?class=assassin&race=fae

I want to make something like this, complete with as you make choices certain boxes of content populate at the bottom of the page.  Yet those boxes would have to be in rows and flow into new rows like content in a HTML div that has set width.  I mean do I go HMTL canvas and pull my hair out trying to learn how JavaScript works in Animate, or go ActionScript and converto HTML/JS, or what?  The problem is I need certain things to show up as people make certain decisions. I'll explain that here:

Image you have items a through z.

If you click icon1, show infoBoxA.

If you click icon4, show infoBoxB (so now we see infoBoxB to the right of infoBoxA.

As you click more boxes, 4 can load before a new row is formed.

Also, if you click icon 1 again, infoBoxA is removed from view, and all the other boxes reflow to fill in where infoBoxA was.

I can get the basics of clicking the circles and having them change color and open the circles to the right.  That is simple gotoandstop(frame number or fram label name), but the above stuff is something I have no idea how to do.

Any help on how to make a page like the onle I've linked would by greatly apprecitated.