GPS Venus638FLPx for novice

Hello,

I am novice with GPS device. I have recently bought a Venus GPS Venus638FLPx. I would like understand the different pins:

1- GND : ground

2- Tx : serial transmission

3- Rx : serial reception

4- 3.3 V : V+

5- 24 : ???

6- 2 : ???

7- 1 : ???

8- PPS: ???

9- VBAT: ???

I didn’t find pertinent information in the datasheet.

Then after having read some topics I have seen that people are in trouble to set the rate at 20 Hz. Does someone have a simple way to proceed ?

Thank you in advance,

Pm