Schematic of a solar charger with chip CN3791

I would like to copy a pcb board that I bought from the market

https://www.amazon.com/Taidacent-Chargers-Battery-Controller-Charging/dp/B089ZVSQ4K

The input from solar is 6V, not 9V or 12V.

I just found the schematic with 12V input:
https://www.electroschematics.com/controller/

but I want the schematic of this pcb for 6V.

Any help would be appreciated.

Thank you.