Arduino + NodeMCU ---- Publishing Data on the Cloud

I didn't read anything in #12 or 16 that was constructive.

But, anyway, my question to you is whether you covered that initial base, sending 'data', in some fundamental form, from the Uno to the ESP. ('ABC', '123'); confirming that you can do that much first.
What's more, this subject is a code desert.
I guess you need to "post your code", the 'transmitter' (Uno) sketch and the 'receiver' (ESP) sketch.
Before you do that, be sure to read about 'code tags' so that nobody has to be a "code tag nag".

All about Code Tags (direct) --

OK, how's this since you didn't get the hint. Don't use an Uno. Use a board that already has WiFi built in. I have only seen one person on these forums who has been happy using an ESP module for a WiFi connection to an Uno, and he is light-years ahead of me in programming experience.

I don't need to take a hint. I gathered your intent: discouragement.

No comment.