Edit order status page and automatically fulfill orders Shopify

I sell account credentials for a game and there doesn't seem to be a great way to do it with shopify. I'm using some license key app thing with works with shopify, instead. It's just kinda ugly and I would like to just edit the text of the order status page and have it provide the account details there rather than just an email providing it. Keep in mind its unique for each order I cant just edit the text once and it be good. Hope I made sense