Both simple and variable WooCommerce products can be configured as membership products.
To create a membership product, simply tick the Membership checkbox and select plans under Membership Plans that this product should grant access to when purchased.
If you want to expire membership after specific number of days, weeks, months or years, enter appropriate value under Membership Expires In and select time unit from the dropdown field.
You should also tick the Virtual checkbox if your membership does not come with anything tangible.
The following icon is displayed in the product list next to membership products:
The same icon is displayed next to each variation name inside variable product edit page.