It most definitely supports HTTP/2. Please see this screenshot:
If you just type
Protocols h2 http/1.1
in you .htaccess it should work. If your browser does not support HTTP/2, it will use HTTP/1.1 as a fallback.
Can you share a URL so we can check?
EDIT: Looking at the screenshot you provided, I can faintly see that you are in the “curl” section. Curl on InfinityFree does not support HTTP/2. Nowhere in the phpinfo() does it say HTTP/2 is disabled.