Contracts (Clients ) link to Products and service

Hi Everyone,

How can i make the under scenario in CRM 2016 in effecient way?

I have a List of Clients and thier related services in an sql database. My goals is that i can see my clients and thier product& services which we deliver to them. How can i do this in effecient way? So later i can see for example: Company test have products ex: 2Terminal servers 10 computers and 2 internet line. and thier payments monthly.

Thanks in advance