I'm Miles from the Social Care team at Shopify. I'll be happy to take a look at how we can remove the work Printify from your catalog.
If you're using a Shopify theme, you'll be able to remove the work "Printify" in your theme editor. Follow these steps to remove it:
This will remove the reference to any vendors from showing on your pages.
If you're using a paid theme and the steps above don't work, you'll need to contact the theme developer directly as they may be able to help out further.
You can make many different edits to your themes. We have a great guide that walks you through the process of customizing your themes. You can find the guide here: https://bit.ly/3lSdEUd.
If you're looking for inspiration, I recommend checking out Shopify Compass. Shopify Compass provides you with webinars and courses on things like store design, marketing and more. It's 100% free for everyone and new content is being added all the time. This program will help you drive more traffic into your store and also convert that traffic into sales.
If you have any questions at all, please let me know.