is 1440p@120Hz on my monitor possible?

Yeah, my bad - its 1440p/120hz OR 1080p/60hz with freesync .

My question is - is it possible to turn on freesync 2 with this Agon monitor in 1440p/60hz on xbox one x?

Is it possible to change the framerate from 144 to 120hz on monitor ( AOC AGON AG322QC4 )
Becoyse what i know is that on samsung c32hg70 it is possible to set framerate on 120hz - so , we can play 1440p/120hz with freesync on

I would look into your monitor and call DELL not Microsoft. I also have a One X and have never had any problems, as soon as select 120hz it automatically drops me down from 4K to 1440p. You must be misunderstanding something about your monitor as there
must be a defect of some sort or your monitor does not support 1440p at 120hz.

For reference, before responding I booted on both my One X's. One is connected to a Samsung 4K QLED and I had no problem switching from 4k 60 to 1440p 120. My other X is connected via an LG 4K monitor and again when selecting 1440p OR 120hz it automatically
selects 1440p or 120hz without any issues.

Until you don't proof me this specific monitor (Xiaomi Mi Curved 34) enables 1440p@120hz with Xbox Series X, your comment is meaningless.

Yeah, there are some monitors with 1440p@120hz support for Xbox series s/x, that simply doesn't mean that ANY 1440p+ monitor with 120hz+ (especially 144hz+) can do it. Period.

I've tried everything, that (1440p@120hz) simply doesn't work with that monitor. I've already listed every step I've tried, I'm not gonna write it again.

Please read previous comments before posting the same dried comments...

No, HDMI 2.0 is enough for 1440p at 120Hz. HDMI 2.1 is only needed for 4K at 120Hz or higher. Although, with certain monitors, 1440p and 120hz can be tricky and not automatic.

What is your monitor model? There could be specific settings (i.e. 'freesync' and 'allow 4k') that could be interfering.