Create A Tutorial On How To Create A Custom Event Allowing Form Fills Information To Flow Into Google Analytics

I need a custom tutorial specific for my website to be able to have the information from a form show up in Google Analytics. My sites form only has one section and it is to enter an email address. I need to be able to see those email addresses, once the users submit them, in Google Analytics. I have seen this work in other Google Analytics accounts but am unsure how to do it. I have Google tag manager on the site. I cannot give access to Google tag manager or Google analytics. Once the project is awarded I will share the site URL. I will use your tutorial to implement myself, will then do a test and as long as the email shows up in Google Analytics I will consider the project completed.