customization – wordpress listing services with multiservice selection search box

I'm looking at several service list topics for example:

https: // preview.

What I should do is select "multiple services" on the home page in the selection box and the prices shown on the catalog page should be the sum of the prices of the selected services. What kind of effort should be required to customize that and how do we customize it?

reference website: https://bookmerilab.com/