I am trying to remove the film artifact on the left of this image. Can anyone help? I am not very good at photoshop. Thank you!
What I would do is try to create a mask for a curves adjustment. In the example below I used the image itself to create the mask, painting most of it black, and using a brush in overlay mode in white to strengthen the inside white parts of the mask.
This is only a start, but it will get you to a point where you could use the clone stamp to paint out the defects left behind, and perhaps use the dodge and burn tools.
There isn't enough data to restore most of the head. You can use a curves layer with a mask to selectively darken the affected area. Where it's completely blown out, you'll have to manually recreate the image. Clone stamp will do the trick on some spots. In others, you may have to paint it in, or borrow features from another photo (or perhaps the other people in this photo).
The end result isn't going to be perfect, but you can make it look presentable with some work.