how to cache website runing plesk panel with Litespeed extenation

Okay again and that is fact. If you want to use Litespeed Cache you need either a plugin or a developer who develops a plugin for your application. Without a development that can organize and control Litespeed Cache you can't use it. Why didn't you ask before you buy a license? Everything you need to know can be read on Litespeed website.....
Depending on your application it could be possible to use cache without a development/plugin. LS Cache allows to define "Vary" cache rewrite rules in .htaccess. Such rules are almost the same like known rewrite rules to redirect a URL to another URL. With these rules you can make cache available, but usage is very limited if there is no plugin for your application available.

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