Brazilian Jiujitsu. The game-like experience distracts me into getting a sweat. There's a whole problem solving puzzle element that is also satisfying.
ClickTeam Fusion 2.5 (the Five Nights at Freddy engine) is a "no code" game engine where you define interactions between the different game parts with essentially a big spreadsheet - your son may be able to tinker with it and realize his ideas in it easily.
The website is not stored on the laptop - those are more like working files. The HTML files (the "pages" for the website) get edited (in this case Dreamweaver) and UPLOADED to the webhosting/web server via an FTP program (FileZilla for example). The domain name (in this case the .org) points to the web server where the web page files are stored.
To just keep everything as is you would need the following from the old website people:
* The FTP credentials to upload the files.
* The webhosting account login to renew the hosting fee (probably monthly or yearly).
* The domain name account login (can be the same as webhosting, but not always) to renew the domain name fee (usually yearly).
Dreamweaver is an out of date program used to edit the (HTML) web page files. It's known as a WYSIWYG (what you see is what you get) editor where you update the web pages as they look (or an approxmiation of what they look like). You could connect to the website via FTP and download the files to any computer and then edit them with Dreamweaver or learn some basic HTML and edit the HTML files using any text editor (such as notepad).
Like many have said you may better off rebuilding the website in a modern WYSIWYG tool. The website is dated but very simple - copying and pasting the content into a software as a service website provider (WIX, SquareSpace, Weebly) which shouldn't take much time and they are easy to use (drag and drop, WYSIWYG). Then you can login to your domain name account and re-point the DNS to the new website and then cancel the old webhosting and not worry about it anymore.
Two of the best mobile games I've ever played are: Total Party Kill & Heart Star. Simple platform puzzlers done very well. Pay to remove ads (if you want) and then there's a bunch of levels, you beat them and the game is done - felt a lot like a good NES/SNES game does.
If you want more of that kind of Zelda seek out the earlier Ocarina-like games. Wind Waker & Twilight Princess were remastered in HD on the Wii U and Skyward Sword was remastered for the Switch.