Mystical and Witchy Photo Background Edit

I’m looking for an expert in photo editing to retouch a photo and change the background to something mystical and witchy. The photo is of my friend and her child, and I’d love to surprise her with this gift. It needs to be whimsical yet beautifully edited to bring out the best of the mystical theme. The source photo is taken on a phone, so please ensure the final quality is high resolution.