Green dot on images and video

Any time you take a photo with a light source in it (like the Sun) or just outside where the light can fall on the lens, with any camera, the light will reflect between elements of the lens and produce either dots like you see or ghost images. This is called lens flare, and is an issue for all photographers with any camera. Here’s an article on lens flare, with some suggestions→What is Lens Flare and How to Deal with it in Photography, but ultimately the best you can do is move the camera around slightly so the reflections fall outside of the edges of the CDS sensor. This isn’t always possible, but it’s the best you can hope for.

Just so you don’t think this is just a problem for your model phone, here is a user tip that shows it can appear in any camera, including $25,000 professional cameras→iPhone Camera Lens Flare and Reflections - Apple Community

There are 3rd party lens hoods for iPhones; there are many camera accessories that can clip over the camera lenses, including telephoto and macro lenses.

And keep in mind that you have a $1k phone with a $10 camera. It’s a very good $10 camera, but it still can’t compete with a good DSLR.