My name is Anne, on the Guru team. Thanks so much for getting in touch with us!
Right now this barcode printer will work for your online store if your business is based in the US and you are using USPS to print labels directly from your admin. It looks like your business is actually based in the UK so this wouldn't be possible through your Shopify admin right now!
You might like to check out these shipping label apps and see if they are compatible with your hardware however, you can reach out to them directly from the app store by clicking Get Support!
I hope this helps and if you need anything else at all please let me know!
I also made an App that integrates with Shopify and prints labels on the Dymo 450. It offers a superior view of Products compared to Shopify (for printing product info labels) and can also print any kind of Order information you need from Shopify.
I would be happy to install that App for you, and you can then customize your labels 16 ways to sundown as you wish.