Mosfet circuit Hints

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I am using an Infineon type to-220 mosfet in my circuit. To "turn it on" I need to ground one of the pins.....which is only low current hence I'd like to make use of the uno. This pin when not grounded is left floating.
I'd like to use a momentary switch, with de-bounce. I've set-up the standard de-bounce sketch on my board no problem and have had a mess around with a few other sketches, BUT I'm having trouble envisaging a way of controlling this ground from the arduino.
The mosfet uses a 24v dc source, and the arduino 5v, common ground. Any time this ground is plugged into the uno board pins it automatically turns on the mosfet. I'm assuming that the pins are pulled to ground. Turning on the switch using the de-bounce sketch has no effect as I guess this only raises the gnd input pin to 5v and the mosfet remains on.
So, can someone give me some guidance on a direction for this project?

The datasheet is folloling link: https://www.infineon.com/dgdl/Infineon-BTS50055_1TMA-DS-v01_01-en.pdf?fileId=db3a3043183a95550118607...
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Are you using an N-channel MOSFET, or a P-channel one?

To turn on an N-channel MOSFET, you drive the gate high, and have source connected to ground, and switch the low side.

To turn on a P-channel MOSFET, you drive the gate low, and have source connected to supply, and switch the high side. But for it to be off, the gate voltage must be the same as the source voltage, so absent other components, to turn off a P-channel MOSFET switching 24V, you need 24V on the gate (typically via pullup from the source) - so to control with microcontroller, you need an additional transistor...

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Not applicable
Are you using an N-channel MOSFET, or a P-channel one?

To turn on an N-channel MOSFET, you drive the gate high, and have source connected to ground, and switch the low side.

To turn on a P-channel MOSFET, you drive the gate low, and have source connected to supply, and switch the high side. But for it to be off, the gate voltage must be the same as the source voltage, so absent other components, to turn off a P-channel MOSFET switching 24V, you need 24V on the gate (typically via pullup from the source) - so to control with microcontroller, you need an additional transistor...
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