Install imagick on Cpanel/WHM
For PHP 7.3 and Cpanel, do this:
On the terminal:
yum -y install ImageMagick-devel ImageMagick-c++-devel
Then on WHM:
1) On WHM go to Home »Software »Module Installers
2) Click manage next to PHP Pecl
3) Select PHP version (in this case 7.3) click apply
4) On the “install a PHP Pecl” box type “imagick” without the quotes and click install now.
5) Wait
https://wordpress.org/support/topic/php-imagick-module-not-installed-or-disabled-message/