Histogram setting problem

[Caitjim Canon]

Hi. I'm new to the R6 Mark ii. I can't work out how to set the histogram to display on the rear screen whilst i'm changing aperture or ISO or shutter speed. What am I doing wrong? It's driving me crazy. Please talk me thru it like a newbie. Thanx in advance.

*** Sorted it - ish. Ive got it working in M but not in AV TV P modes, Is it not available in Av or TV ?