Can anyone recommend a commonly available 40MHz crystal for use in a custom designed board using the ESP32C3-FHN board and what value capacitors to use with it?

Hi Can anyone tell me what the ideal output impedance is for a circuit that is to feed its analogue signal into an analogue input on the ESP32-C3? I can't find that information in the data sheet. I am planning a voltage divider to read the voltage from a single cell Lipo and was going to use 220K Oh...