Create a Squarespace Site, then transfer domain and redirect pages

I currently have a website through Shopify (let's pretend it's called www.getoutside.com). I am closing down the Shopify site in a few months, but am creating a blog on Squarespace that I would eventually like to transfer the domain to. I want to get the blog up and running before I close down the Shopify site, so I was thinking of using a temporary url (let's call it www.getoutsideblog.com)..

Here's my question: when I shut down the Shopify website, can I keep everything I've worked on with www.outdoorsyladiesblog.com and change it to www.outdoorsyladies.com and create 301 redirect pages so that I can use my original domain, but keep all the work I've been doing on the blog?

I realize this might be confusing, so happy to clarify! Thanks in advance for your help!