Using Mac mini fully, with iMac as monitor

I think this has been asked elsewhere but only in parts, so here’s my question.

I have an old iMac late 2009 which has a mini display port at the back.

i plan to buy a current model Mac Mini, and use the above iMac as a monitor.

While doing this I also plan to use my existing Apple keyboard and mouse.

I don’t need speakers as I have a focus rite sound card and external speakers and headphones.

My question is 1. Can I use the iMac as a monitor for the Mac Mini using mini display port. Will there be lag. 2. When I do this will I need two separate keyboards ... one for the iMac F2 function and one for the Mac Mini for regular use. 3. What about mouse. 4. Where do I connect my sound card and other peripherals - to the Mac Mini I assume?

The idea is to pretend that the iMac is just a monitor and plug everything else into the Mac Mini. Is that possible.

My use is primarily for recording and making music using Logic Pro, which I will run off the new Mac Mini so I need a stable set up.

Any help would be appreciated.

Thanks!

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