Everyone has been given an ad account when they first created their profile. You can access your ad account at any time by typing this address into your URL or clicking this link: 


This will take you to your Ads Manager where you can create ads, set up billing and payment options, create custom audiences to target and track every metrics about your ad up to the very beginning.

Link to Video Tutorial > 

How to: Set up Facebook Business Manager and Ads Account 2018 https://www.youtube.com/watch?v=lOticdFxpx4&t=22s