Need help designing a sketch to use with the ESP-01

I am doing a personal project. I am not freshly new with Arduino, but still in the early learning stages. I have a mega outside in my garden connected to 10 Hygrometers and 2 DHT22 sensors. I have an ESP8266-01 module that I've been testing on an uno using the AT commands and I don't understand how those can be used to send the data to my pi 3. I want to use the Arduino as a server and send the data over my home wifi to my raspberry pi 3 inside and display the data in a spreadsheet of some sort. My problem is that I'm confused by all of the examples out there that send to a web page, I don't want to go outside of my home network. I've looked into MQTT but all of those use the Arduino as a Client and not a Server or sends out to a web page and back to a Pi. Can someone please help me start a simple sketch to send data to my Pi on the same network? I want to use my ESP as both STA and AP so I can retrieve data but also modify my sketch from inside my house.

The beginners guide to the ESP shows how to program the ESP using the Arduino IDE. Programming with the IDE allow much greater flexibility than the the AT commands. The beginners guide has lots of information on using the ESP in a network. Then you can connect he Mega to the ESP with one of the (3 extra) hardware serial ports.


Other thread removed.

If you had read the forum stickies no one would have to explain. #13 of this post.