Download the PHP 7.4.x/8.0.x zip/rar version from the PHP Download site for Windows x86. Choose the x64 Thread Safe version if you have 64bit Windows. As of now PHP 8.0.1 is available so I have downloaded PHP 7.4.x/8.0.x(Latest Version).
Copy to your UWAMP directory, (Eg. c://uwamp/). Go to C:/uwamp/bin/php and create a new folder “php8.0.9″ (if folder not exist)and extract the content of downloaded php .zip file here.
Done.