1.7 how to manage shared products in some shops?

[Sandeep Singh CH]

Hi
I have prestashop 1.7 multishop store. now I am using 4 shops which has stock shared. Now I want to add 2 new shops.
my question is: because into these new shops we will not add all the products we already sell in the other online shops what will happen when we will have to add new products? I mean we want to add more products into 4 old shops  but not into 2 new shops
how can we do this also when we have to change a product (I mean change the description) but this change should be added only into 4 old shops
and the second question is: can we have a different stock into the shop example.co another different stock into example.es and another different stock into 4 old shops for the same product?