How do I connect a LEGO wheel to axles so it can be powered? I have a growing LEGO collection, which started with a lot of parts from the generic 10697-1 'LEGO Classic Large Creative Box' set. Sometime later, I bought a bunch of wheels, part numbers being: 55981 and 6014.

My question is, how do I connect these wheels to axles (e.g., 3706) in such a way that the wheel can be driven by power functions (e.g., by a LEGO motor/servo)?
Normally when wheels are powered using an axle they have an axle hole, whereas your wheels have a pin hole, and a 3mm mini pin hole.

So you should probably buy some wheels with axle holes anyhow, for future building.

However, in the meantime, there are tricks to driving parts which use a pin hole, for example, a lego 55981.

You simply use either this, or this and this

There is also a 2L pin version here or a 2L axle version here

There are other clever ways to do it too but this should be enough to get you started. I am not familiar with a way to drive the other wheels you mentioned
unless I have forgotten a way, these are not really designed to be driven at all nor easy to be driven because they have a 3mm 'mini' pin hole, which fits into a 3mm 'mini' pin.

The reason I say 'clever' is because these friction pins act as clutches, if there is not enough torque required to drive the wheels then they will slip and rotate independently of the wheel.

If there is sufficient torque then they will grip the wheels pinhole and drive it.

This has both positive and negative effects depending on what you're doing.