Hello and welcome to the forum.
The answer is both yes and no. With the standard version of Monarch, you cannot open an Excel file directly as a datasource. You can with the Pro version. But that still wouldn't get you a one-record-per-line view that you're likely seeking.
Instead, open the document in Excel, and save the worksheet in question as a text file. Try the "Formatted Text (Space delimited) (*.prn)" file type. I like that one as it works very well for Monarch.
It's a bit of an extra step, but it should get you to where you want to be.