You have a table A with new data, and a table B with old data. How do you make sure table B is refreshed with data from table A? You want to insert new records, update existing records and to delete removed records.
The T-SQL merge statement can do all that for you.
How do you get records from a SQL Server table into a MSMQ queue as separate XML messages?
A commonly suggested way to communicate with MSMQ from within SQL Server is to create a CLR assembly. See for instance this article that has a great coverage of how to use CLR in this scenario. Note however that you have to import the System.Messaging.dll as unsafe for this to work. And you have to enable CLR obviously.
If this is not an option, another way to do it is to use PowerShell. Which is what I will cover in this demonstration.