Consider the image below, taken with a phone camera. There is a white spot near to the Sun, which is dependent on the orientation of the phone. I know it is not a planet nor some sort of star but it arises while we click photo of sun through camera? (It is day time photo)
The white spot is known as a lens flare. This is a general term for spots or streaks of light in photographs caused by unintended reflections of light within the stack of optical components in a camera. This can be from light sources inside the image frame but also from bright sources outside of the frame, and it can come from both single and multiple reflections within the optical stack. Most optical components have anti-reflection coatings that make reflections very weak, so they're not normally imaged, but if a light source is bright enough, even the weak reflections that get past the anti-reflection coating can make it to the detector at appreciable brightness.
Because of this, the precise details depend sensitively on exactly what optical components are in the camera and how they are arranged, so producing a diagram for how each individual flare was produced requires a detailed knowledge of the camera's internal geometry and the position of bright light sources outside it.
In any case, for the image you've shown, it's clear that you're seeing lens flare coming from the Sun. If you want to verify this, go back outside on a sunny day and reproduce the white spot, and then use a finger to block the sun from the view of the camera. The lens flare should disappear as you do so, and if you only partially block the sun, it should reproduce the shape of the blockage.