Anything below the 48-50 inch range is going to limit you to pretty basic offerings. I'm not sure if HDMI 2.1 or 120Hz is available on any TV in that size range yet, nor do I have much advice other than I would probably stick with Samsung or Sony. If you want to splurge get a 48" OLED from LG.
The 5 Best 40-42-43 Inch TVs - Spring 2021: Reviews - RTINGS.com