Usage documentation

Thanks for the contribution of this module. After searching for a long time, I still do not know how to use it. I can easily add a currency field but do not know how to implement other functions, such as currency conversion. Do I need to retrieve the currencies and exchange rates stored in this module to convert the currencies stored in a float field in my theme? Thank you!

I'm also 100% lost on how to use this module.

My use case is simple: I need a "price" field where users can enter a price with currency. Same as in Commerce. Has anyone figured out if this module can accomplish this?