Buy a TV, pay attention to what?

I want to buy a TV in 75 inches. Brand should be Samsung.
What should I pay attention to here?
There are so many different TVs in 75 inches and a range from 800 euro to 2500 euro. What do you have to pay attention to? I like to watch a lot of movies so it is important to me picture and sound. I also use many apps like Netflix or Amazon Prime or DAZN.

For me, an important criterion for a 75-inch giant would be that it offers 4K resolution and dominates the H.265 codec, as well as Dolby Digital. The speakers should deliver at least 10 watts each at this size. In addition, I would not want to do without a triple tuner, so that both cable and satellite reception is possible. WLAN would not be bad either, since you want to use Netflix and Prime Video. In addition, I find at least 2 HDMI ports mandatory.

If you want to hang the device against the wall, make sure that the device is subject to a https://wandhalterung-blog.ricoo.eu/was-ist-vesa/. Many wall mounts are designed for this standard.