I'm a total newbee to all this... Phono vs Preamp?

Ok, I realize that before a turntable's signal gets amplified it needs to (1) get EQ'd and (2) be brought up to Line level. I currently use a decent receiver that has a built in Phono Stage. My turntable also has a built in preamp, but I don't use it.

I've been looking at getting a decent tube preamp to fool around with, but I want to get this straight before I buy anything:
If I hook my turntable into a preamp that does not have a phono-stage, can I still hook that into the Phono section of my receiver? Or will that be too much gain?

Could I switch on the preamp on my table, or would that be too much gain?

Or would I need to get a phono stage on it's own?

Let me know, I'm a tad confused.
Yes, way too much! The phono section of your receiver is set up for seeing an output of a few millivolts. The preamp output is in volts. You can hook the phono stage on your table into your preamp and then into a line level [tuner , etc.] input on your receiver. If you do this use the tape out outputs on the preamp as this bypasses the volume control on the preamp. My advice would be not to do it, the improvement in sound is uncertain. I would wait until I was ready to make a major upgrade to the whole system. If your receiver has a" preamp in" set of inputs I would consider it, otherwise you will be using 2 preamps in series and the one in the receiver will be the weak link.
What about running it into the Tape Return?
I'd suggest just getting a pre-amp with a suitable phono stage built in or separate.

The main thing would be to know what kind of cartridge is used on the phono, ie ceramic, moving magnet, Moving Coil (hi or low output)?

If it is ceramic, I'd start off by considering a new table and cartridge and go from there.
I'm using a shure m97xe -- Moving Magnet.
You could use tape return , I haven't used a tape recorder since the 80s so my knowledge of tape inputs has some dust on it. Look at your receiver specs and see what the sensitivity of the tape input is. Doing this is not the same as having a preamp in, when you have this then you are bypassing the whole preamp section. When you use the tape in you will still be using 2 preamps.
And that is how bad? Or does it just mean I'd lose fidelity, as I'd just be adding an unnecessary component to the chain?
If you buy a tube preamp without a phono section, you can plug your TT into your receiver, and take the tape out from your receiver and feed it into your new preamp. Ultimately, you probably want to eventually just get a decent stand-alone phono stage, or get a preamp with a phono stage included.
But then you would have to feed the output of the preamp back into the receiver. The whole question here is just what are you trying to accomplish? The idea of getting a superior component is removing the inferior one from the chain. The benefit of the better component is greatly lessened if not removed entirely if you still have the worse component processing the signal. The chain is only as strong as it's weakest link; just adding a better unit somewhere in the chain does not somehow magically transform the sound.