How can I create a spreadsheet with formulas?

I want my clients to be able to fill out the form and get results based on the formulas that I already created.

I have an .xls document that I will like to make a form

We have a Spreadsheet widget, which allows to enter calculation formulas for input cells:

Please follow this guide to add a widget: How-to-Add-a-Widget-to-Your-Form

Also, Input Table element allows to set up some calculations, here is our guide: How-to-Perform-Form-Calculation-in-the-Matrix-Field