Ash here from the Shopify team. Welcome to the Shopify Community!
It's exciting to hear you're planning to start up a shop with Shopify! I'm glad to share some resources with you to help get started. To address your initial question first, in order to sign up for a free trial all you need is an email address. Further down the line when setting up a payment gateway, etc. you'll be required to provide some additional information such as personal/banking information, but that would be variable depending on where you're operating out of, and what payment gateway(s) you use.
We have a free Shopify Compass course to teach you everything you need to know about Shopify and how you can get started. Feel free to check that out here. We also have a free 14-day trial you can use to see if it’s the right fit for you. You can sign up right here.
What kind of business are you wanting to start?