I’m trying to create a Reservation App, I have create several Database: Services which is the main one, and a database for each services.
The Issue that I have right now is trying to properly link the databases so when I click on the main page for the Service it open in a page where I will see a detailed list with all the Options of an specific Service.
How can I do this? I’m trying with collections relationships however I cant figure out how to do this
Welcome to the community @maiky051018! 
This is like Categories and Sub-categories right? You don’t need many collections. Just 2 collections needed! One for Main Services and one for Sub Services (Options). Then create a relationship between them. So a Main Service can have multiple Sub Services and a Sub Service can have one Main Service. If the Sub Service should linked with many Main Services then create the relation as, Main Service can have multiple Sub Services and a Sub Service can have multiple Main Services.
Let me know!
In my case each Sub Services will have different options, some Sub Services will have from a minimun of 3 Options and other Sub Services will have around 6 options that the customer can choose.