Salesforce's Account & Opportunity Teams allow you to associate multiple users and roles with one Salesforce record. You have the option to:
Assign team members individually on each record
Create default account & opportunity teams (useful if the same AE and SDR work together on all opportunities, for example).
Automatically create Account/Opportunity members based on criteria on the Account/Opportunity. A common example we see here is assigning different CSMs to an Account based on Employee Size or revenue.
If you want to auto create account/opportunity team members, please specify the Salesforce user(s), role(s) and criteria for assignment.