This post explains how to create a new related contact when account is inserted in salesforce.
⇒ " This trigger creates a new contact(With same account name) whenever new account is inserted ..Number of new contact created is depend on NumberofLocations__c(Account field) and all contact name will be Team_AAA"
Here I've created one new Account with name Microsoft with NumberOfLocation equals 4
After insert this account trigger will fire and create 4 new contact with name Team_AAA with account name Microsoft
Thanks,
Lovesalesforceyes.