How to change color to transparent in photoshop

Question

Working with color

Hello! I'm not very familiar with Photoshop, and in the absence of a designer, I need your help in this matter:

There is a picture

The scarlet color dominates on it. It is necessary to change this color to transparent. This is necessary in order to be able to put a different color or background image under the image, which would "shine through" through the transparent areas of the original image.

Answer 1

As an option:
1) Draw circles with the ellipse tool. Merge them into 1 layer (Ctrl + E). Then right click on the layer and Rasterize layer.
2) Circle the girl - for example, with the polygonal lasso tool. Select the layer with circles - then Select-Modify-Feather (specify how much px to smooth the selection - the circles are feathered) and press Delete.
3) Ctrl+click on the icon of the layer with circles (so that a selection appears), then select the girl and delete.
Save as png.