For a project I have to use a voltage level shifter. On both sides of this shifter I have to specify the target voltage. Thus my idea was to simply set one pin on high (3.3 V) and use that as VCC on one side. My question now is if that is sufficient, or if the Pi does not produce enough power for powering the shifter. Could I damage the Pi with that configuration?
I assume you are using a MOSFET Level Converter. You won't damage the Pi as the reference draws little current, but it won't work properly as the high level will be <3.3V. Why not use the 3.3V?
It depends on the amount of current that draws what you connect the pin to. I would not go far beyond 30mA