Battery charging and precentage in Arduino

Hello, I’m using the XIAO nRF52840 with a 3.7v li-po battery connected(see the photo).
I’m using the board with an app that I build via Bluetooth and I want to see the battery precentage and also get an indication if its charging or not. I searched the internet for help but didnt find something helpful, hope you guys can help me.

I can’t post any circuit. But I can share an idea. You can make this type of board featuring the XIAO.

This design features an ESP32. You can redesign such a board with the XIAO.

Hi ,Smartlscar:
I don’t think I can support you on this issue, but I can offer some suggestions about Battery charging and XIAOnRF52840:
when using XIAO nRF52840 (Sense) for battery charging。When P0.14 (D14) turns off the ADC function at a high level of 3.3V, P0.31 will be at the input voltage limit of 3.6V. There is a risk of burning out the P0.31 pin.
Currently for this issue, we recommend that users do not turn off the ADC function of P0.14 (D14) or set P0.14 (D14) to high during battery charging.