Hey @subbu, welcome!
Yes, you can use the GP-20U7 GPS receiver by cutting its JST-PH connector and connecting it to the second columns of female I2C pins available on Carloop. You will need to check which wires on the GPS correspond to which pins on Carloop (TX, RX, Power, Ground). The one we recommend is GP 735 from Sparkfun. You can connect this one directly to the white connector located in between the two headers. We've added an example on how to use it on Carloop's Github readme file.