ImageMagick
Windows
Find PHP version.
php -i | find "PHP Version"
Find if PHP use thread safe or NTS
php -i | find "Thread Safety"
Download from official website
Download ImageMagick DLL from ImageMagick binaries like ImageMagick-*-HDRI-x64-dll.exe (with CPU 64 bits) and install.
Download with scoop
Alternative is scoop but, when I write this guide the download link is broken.
scoop install imagemagick
Install imagick PECL
PHP use interface to use ImageMagick, this interface works with PECL. You have to download last version on PECL. Choose your PHP version with thread safety and architecture. For me, it's 7.4 Non Thread Safe (NTS) x64 for PHP 7.4 NTS.
Extract the archive, find php_imagick.dll and put it into ext directory of your PHP version. Like C:\Users\USERNAME\scoop\apps\php7.4-nts\7.4.30\ext for my version.
When DLL is in extensions, you can edit php.ini in C:\Users\eriviere\scoop\apps\php7.4-nts\7.4.30 to add extension without php_*.dll.
extension=imagick
You can find your php.ini with this command.
php --ini
Check if ImageMagick works with PHP
Restart your terminal.
Try to find imagick in the output of this command.
php -i