Creating a workflow by trigger which sends automated introduction message to all new clients

Hello,
I am looking to either create a workflow or possibly an app which by trigger will send a automated sms “introductory package” of scripted text and screenshots in sequence to all new client’s. I’m new to the zoom developer platform and do not know where to start. I do know how to use visual studio code and MongoDB. Although, I’d prefer to keep it simple, if possible and not turn this into a coding project.