Word has a drawing pallette that would allow you to do something simple like that
View --> toolbars --> drawing
Just use the circle tool and then add in the initials via a text box or word art.
Then select both the circle and the text, right click, grouping --> group
This will make "lock" the items together so its easy to move around and/or insert into another document
Quite frankly though its prolly easier to just make a drawing in MSPaint or an actual image editing program and then save it as an image which u can import into word documents