Calculator - heat pumps / JS, API, XLS

I will commission the preparation of a calculator for a website.

I have a graphic design.

Half of the calculator is to present the calculation path based on the API https://cieplo.app/start

The other half is to expand the options available in the API by:

- o model selection

- calculating the ratio of nominal power to demand

- drawing a graph

- minimum temperatures

- bivalent point

- tank selection

calculator to be available to the user without logging in

logging option for the installer:

- send offer to email

- save offer

- edit offer

Looking for a person who:

- has experience in working on calculators of this type. Ideally, as if she used to do a calculator that calculates thermal power to heat a house.

- API https://cieplo.app/start is clear to her

- is familiar with XLS (advanced formulas) - I have a model calculator ready in an XLS file