Based on the description and the picture showing that it writes digits into notepad I will assume that this reader just identifies as a "Keyboard" ( USB-HID-device ). ( Similar to many 1D/2D-barcode readers for example. )
And will most like work just like that when you plug it in. Present RFID tag and this reader "types" the ID.
NOTE! This reader will probably never be able to read more data from the tags than just the UID ( Unique ID ), if you want to explore NFC or store information on Mifare Tags then this reader is probably not for you.