If one absolutely does not want to install or configure anything, tryapl.org has both a keyboard, a clickable "Primer" with explanations, and the ability to use backtick ` as escape character for APL.
For installs, Dyalog has two IDEs which both figure a language bar.
@ATaco Well, I guess you can type these: ~!@#^&*()-×=+.{}[]|\/?':;,¯←→↑↓
The very basics: any folder can be treated as a misite. Loading the miserver workspace, and entering Start'folderpath' will start the site on localhost:8080
using a browser to navigate to localhost:8080/somefilename, will cause MiServer to send that file.
Now a special thing with MiServer, is that if the requested page has the extension .mipage (this is configurable) it is treated as an APL script.
Basically, it has to be a class with a method called Compose. This method has APL + MiServer's extensions to build the HTML, CSS, and JavaScript for the page. Parts are just thin covers for HTML, but others are powerful APIs that will create entire HTML structures with one short APL expression.
E.g. ∘.×⍨⍳10 will create a 10×10 multiplication table (matrix) in APL.
To add this table to the webpage as a proper HTML table, just add the line Add _.Table (∘.×⍨⍳10) to the Compose method.
No need to worry about html tags like <table> <tr> and <td>.
See it in action and click the "APL code" tab to see the the APL that generated the page.