if you are playing with your friend on the same local network, port forwarding is not required. However if both of you are in different network, port forwarding of the host will be required:
How to port forward:
I don't play in PC with wi fi I mean I don't use any routers, I use my mobile data and play in phone. Should I send my phone's ip address to my friend?
If you are using a phone, you can play with your friend by opening a hotspot on your phone and ask your friends to connect to it. This should form a local area network (LAN) and allow connection between the devices. I don't think you even need to enable data for LAN connection to work.
Of course your friend must be 8n the range of your hotspot