can someone help me
can i connect sim900 With arduino uno hardware serial port(not software serial) (pin 0 and 1) if so can give me code plea
Problem is if you do so, it will interfere with your computer serial. So all communication to the SIM900 comes to your Serial monitor as well.
If you want to use hardware serial, get the right board. The Leonardo is very similar to the UNO, but has a true hardware serial port on 0 and 1 not conflicting with the USB serial to the computer.