Imac and macbook Pro - Help Please

[Flyer2020]

Just bought a 2021 14" MacBook Pro and I wondered if I can use my 27" mid 2011 imac as a monitor? There appears to be some conflicting reports about the 27" not working but 21.5" does.
If the 27" does, what cable would I need.

Many thanks in advance

 

[hg.wells]

Here is the official list:

Use your iMac as a display with target display mode - Apple Support

Target display mode is a feature available with certain older Mac models.

support.apple.com

 

[Scottyk9]

My understanding is your 2021 MBP is too 'new' to be able to use an older iMac as a display.