Hey there, Shimondthedimond!
Bo here from Shopify Support.
That is a really great question. The sidebar can generally be turned off in the theme customizer itself. You will need to do the following:
If you are still learning the ropes of Shopify I'd recommend taking a look at our Shopify webinars for sure. These short tutorials takes you through all the basics of creating a store such as adding products, variants, collections, theme changes and pointing a domain to your store. You should be able to sign up here http://bit.ly/2SVZC6w if you would like. We also have a free business course with our Shopify Academy that I would really encourage you to look at if you get a chance: http://bit.ly/2Qt6Ay6.
Let me know how this goes and if there is anything else I can assist you with, I'm happy to help!
All the Best,
Bo | Retired Staff Member