I was wondering how I can create a Shopify website purely offline for the purpose of learning the settings, how to edit, and install applications and programs. If there is such a thing that exists, can I also import our current operational website into it so I can experiment on what we can do with the shop? We already have a website operational and running but I do not want to mess with anything in it.
Yes, it is possible, you just need to create a developer account. Take a look at this video for detailed information.
If your current website is already on Shopify you just need to download the Theme and then upload it in your developer account.