Using Automation to onboard new member?

Has anyone used Automation to onboard a new member?  We're considering using the automation to do so, but we have yet to confirm it's possible.

Someone signs up for a new account, and we'd like to email a message welcoming them to the site, and then after a period of time send them a second email, and probably do this up to 3 different messages.

We might be open to using a PM instead of an email.