Is there any way to communicate between MangOH red and Raspberry Pi 3?

I have MangOH red board alone, I want to interface Raspberry pi 3 and MangOH with the help of SPI, UART etc just using GPIO of pi. can anybody help in this?

Do you have a wp module on the mangoh red?

Yes.I have WP8548 on MangOH RED

You can use UART or I2C to communicate with the Pi.
For i2c here is some sample code:
https://github.com/mangOH/mangOH/tree/master/samples/tutorials/mangOH_Red/i2c/BatteryChargerReading

will it work for pi3, I see that the sample code is using the Legato framework, So it is possible only with legato? I want to try without legato, do you have any possible solutions?