Can I use my mid 2011 iMac screen with the Mac Mini M2?
Can I use my mid 2011 27" iMac screen as a monitor with the Mac mini M2?
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Note the very limited hardware and OS requirement for Target Display Mode in this Apple article:
Use your iMac as a display with target display mode - Apple Support
especially this requirement for the Mac that is the video source:
No Apple Silicon/M-series Macs are supported.
You may be able to use a third-party product like Luna Display or Duet to accomplish this, but I have no idea if the image quality and response times will be satisfactory for your needs.