What I like about SharePoint is that sometimes it fills like a Swiss Army Knife. It can do it all; you just need to configure it properly. One of the common requests I have been getting over the years from clients and my loyal blog followers was the requirement to use SharePoint as CRM (Customer Relationship Management) software. I will be upfront;
if you are looking for sophisticated functionality, workflows, etc., you will be better off using a third-party CRM. However, if you just want to store and organize basic information on your contacts, clients (customers), and deals/opportunities, you can use SharePoint, with a bit of configuration. So below, I would like to outline the steps on how to properly set up a CRM in SharePoint Online by using just the out-of-the-box features .
Step 1: Understand the limitations
Step 2: Create lists of Clients, Customers, and Deals
Step 3: Create a Document Library for Client Documents
Step 4: Embed all the lists and libraries onto the same page
Step 5: Set up Dynamic Filtering
The result
https://sharepointmaven.com/how-to-build-a-simple-crm-in-sharepoint-online/