There are a number of ways to change video format on Android. The most common way is to use a file conversion app. These apps allow you to select the video format you want to convert your video into and then make the conversion. Many of these apps also let you select a specific resolution or quality setting for the output video.
Another way to change video format on Android is through a dedicated video editing app. These apps usually have more comprehensive features than file conversion apps, and they may be better suited for certain types of conversions. However, they can also be more complicated to use.
Finally, some newer versions of Android include native support for certain types of video formats. For example, the latest version of Android supports HEVC (High Efficiency Video Coding) out-of-the-box. This means that you don't need any special app or converter in order to watch videos encoded in this format.