If you mean "abc123 above the barcode" then change ^BCN,100,Y,N,N
to ^BCN,100,Y,Y,N
.
If you mean "Print 'Nabeel' above the barcode" then insert
^CFD^FDNabeel^FS
^FO20,50
After the ^FO20,20 line.
This would select internal font "D" (CFD) and print "Nabeel" at offset 20,20 (the preceding (^FO)) then set the position of the barcode to 20,50 since 20,20 is really close to top-left of the label.
I'll presume you know how to modify your program code.