I have just bought QuickBooks I have customised my own letter and also a dummy account. I cannot find a way of combining the two together as one document

Welcome and thanks for posting in the Community, @charlietl.

To ensure that I'm on the same page, may I know what you're referring to as a "letter"? Also, when you say dummy account, do you mean QuickBooks Online (QBO) account? Any additional information will help provide the best resolution for your concern.

Simply click the Reply button below to add more details, and I'll get back to you right away.

I'm looking forward to hearing from you soon!