If you're selling a product (or offering it for free) and you want that order to give clients access to extra products, there is an easy way to do that with product automations.
Examples:
Go to settings of any product (Products page -> click on a product) and look for the section called Automations.
Product automations allow you to do a few things:
In the selector pick an option, for example Give access to a Course, and then you'll be able to select which course you want to give client extra access to when they complete the order for the main product.
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