I dont know how to use equipment and how do I contact a person at square support?
Here's the Get Started guide: https://squareup.com/help/us/en/article/5123-square-get-started-guide
If you have a specific question, I'm sure someone will be able to help here if you ask. If you run really stuck and need to contact Square directly, visit https://squareup.com/help/us/en/contact
Square Community