Feeding external data into my dataset, JSON

Say I’m using an email parser, that puts data into an excel or a google sheets page. How can I upload these to my Wix dataset? How would you do that?

So my parser can send me the info via form post, json or xml. What is the best option for me to receive that data? which function?
I can’t fetch the info, as it is sent to my url.

Thanks in advance!

Can I get my data set address? Does wix support mysql?