Read the viewing offer's quality label
Resolution belongs to the video edition, not the poster. A film listed on Openload can have different available qualities across services or countries. Check the actual offer, your plan and your device. A high-resolution display cannot create a native 4K source from a film supplied only in HD.
Prefer a stable picture to repeated interruptions
A phone on a variable connection may work better at a lower setting than a large television on a steady connection. Adaptive quality, when available in the chosen player, can respond to changing bandwidth. If it keeps shifting in a distracting way, try one fixed lower setting and observe whether playback improves.
Resolution is only one setting
Subtitles, sound output, display brightness and the source's compression all affect the result. High dynamic range and surround sound are separate capabilities with their own device requirements. Read the player's options and test a short scene. Openload helps identify the production; the viewing service supplies and controls the actual stream.