Help needed Iiyama Prolite G2773HS

Hello everyone

I recently bought the above monitor but I'm not very happy with the default settings because the display is too bright and also almost impossible to display a fairly solid black. I've spent some time reading a few reviews which are in general agreement with this issue. However they then explain that in order to get the best out of what is a decent monitor it must be calibrated.

After exploring the menus found that Clock, Phase and Sharpness are greyed out and are not accessible. Also cannot find any colour setting that will give me 6500K, to set Gamma to 2.2, etc. Being new to this sort of thing I was wondering if anyone would happen to know if there is a tutorial somwhere that explains how calibrate this monitor, or any useful advice, for which I would be most grateful.

Thanks

Joe