Microsoft Sharepoint and Teams efficiency review

We are a growing accountancy firm who use SharePoint as our document storage solution. We have used Teams a bit to keep internal notes and for internal messenger but we are looking to pull it all together properly and see if we can create some efficiencies with our use of other Office products (Excel, Word and Outlook).

Its a case of knowing we are not using Office 365 in the best way and needing guidance on how we can use it better, both within our company and collaborating with clients too. We use each product in isolation and they we assume they could be far more integrated.