You should power it from P1.01, not from the USB port (which would require a custom cable anyhow).
P1.01 is the one that has "P1" next to it, on the outer corner of the header.
With Rev A4 boards, the USB-A port will remain without power when powering from P1.01. Rev A5 fixes that. There are two workarounds for Rev A4 when you want to both retain the use of USB-C and retain a working USB-A while powering externally:
- power via P1.05 with a Schottky diode in series (instead of P1.01)
- a rework (cutting a trace and soldering a wire)
