what kind of license?

Goodmorning everyone,
I need to redo three sites in WP with a single theme (two of these are subdomains of the other and one of these will have to support woocommerce). To do this, I would first need to work on these three sites using a free hosting service and then migrate the three sites to the correct hosting. Which and how many types of licenses for a theme should I purchase? forgive me for my bad english, thank you so much for your attention!

Are the subdomains connected to the main site e.g. blog.website or are they something separate?

All subdomains are connected to the main one (ie shop.website and product.website, where “product” means a specific presentation page of a particular shop product) and in each of them there is at least one link that refers to the other

Regular and one license should be ok but your best option is to ask the author esp. if you plan to set it up then migrate to new hosting which will mean deregistering etc.

The author will be able to confirm this is not going to be problematic

Thank you very much for the advice, I’ll do this way. Have a nice day!