Solve AH10034: The mpm module (prefork.c) is not supported by mod_http2

Complete error.log line:

[Sat Jun 13 15:57:54.049273 2020] [http2:warn] [pid 23029] AH10034: The mpm module (prefork.c) is not supported by mod_http2. The mpm determines how things are processed in your server. HTTP/2 has more demands in this regard and the currently selected mpm will just not do. This is an advisory warning. Your server will continue to work, but the HTTP/2 protocol will be inactive.

You would need to change mpm loaded module:

vi /etc/httpd/conf.modules.d/00-mpm.conf

Comment this line:
#LoadModule mpm_prefork_module modules/mod_mpm_prefork.so

Uncomment this line:
LoadModule mpm_event_module modules/mod_mpm_event.so