Use Powerboost while machine is Off

Hello,
So i am currently working on a project in which i have to incorporate a key switch and a lipo battery so as when the key is ON the arduino takes in the main power from the 9V battery, if the key is off and two wires/pin on the powerboost 1000c are connected(need help with which ones) the arduino will power on using the lipo 3.7 V battery

Below is my schematic diagram. Can you please tell me what goes into Vin pin so i can turn on the arduino while the key is OFF. Any other solutions are appreciated.

Can you describe what you're trying to achieve here, maybe in more detail?

I think we need a little context to make sure we're not in X-Y problem land.

Because when I look at this, I see what appears to be a 9v battery (please tell me not one of those rectangular smoke detector batteries) charging a LiPo battery (based on the fact that the file is called "charger diagram" I deduce that the powerboost1000c charges the LiPo?), and that's a red flag to put it mildly.

HelloArduinoWorld:
Hello,
So i am currently working on a project in which i have to incorporate a key switch and a lipo battery so as when the key is ON the arduino takes in the main power from the 9V battery, if the key is off and two wires/pin on the powerboost 1000c are connected(need help with which ones) the arduino will power on using the lipo 3.7 V battery

Below is my schematic diagram. Can you please tell me what goes into Vin pin so i can turn on the arduino while the key is OFF. Any other solutions are appreciated.

OP's circuit:

It seems like it might waste energy, but it should charge the LiPo. What are the "Bat Pin" and the Arduino's "Vin pin" hooked to?

ps, the "Powerboost 1000c" is this, or a clone, right?

They are floating right now( dont know what it should connect to) also it is the adafruit powerboost 1000c