HDR movies

You should be able to get the HD version without HDR. If you download in the Apple TV app, then first check the Preferences for that app. There is an HDR checkbox to uncheck. There is a Download Quality to specify.

How do you get the downloaded movie from the notebook to the TV?

and choose lower streaming quality.

The Streaming Quality is for when you get the playing content directly from the internet. It doesn’t apply to downloads. Hence the separate Download Quality option.

Playing using HDMI cable. I checked the TV it does support HDR but still the apple TV app says it can't !

The HDMI adapter is probably limiting the HDR capability. You would need an HDMI 2.0/HDCP 2.2 capable adapter for HDR support.

You would need to make sure you are purchasing the SD version. I would suggest contacting iTunes to see about getting a refund and then they can walk you through purchasing the right version.