SenseCAP Home Assistant Yellow Setup

I am following the Home Assistant X SenseCAP Indicator | Seeed Studio Wiki wiki page but am getting stuck. I have got as far as Project Configuration, but this is where I get stuck.
How do I edit indicator_ha.c files? Where are these located?
It says “After completing these steps and building it, you should be able to see the Home Assistant and Indicator working together.”
but there is no steps or explanation how to do this!
Please help.