Getting the right hardware & software

I am brand new to Arduino. My project is to be able to monitor, real-time, the water flow through my residential drip irrigation system. I purchased a "Hall effect" water flow sensor which I intend to install on the main irrigation line. I intend to connect the sensor to an Arduino board to be located within my garage within range of my WIFI network.

I believe that the Arduino Uno is the appropriate board to use. I note reference to two different WIFI shields: WIFI shield and WIFI shield 101. I assume the former is no longer available and the latter, WIFI shield 101 is currently out of stock. Am I correct so far?

With regards to IDE software, I have noted conflicting recommendations. One recommendation is that only version 1.0.3 should be used withe the WIFI shield. The second recommendation is to use the latest IDE. Which is correct?

Once I can settle these issues. I will return to the Forum with more guidance questions.

I would go for an ESP8266 for connecting to wifi. There's tons of info out there for them and they're cheap as.

Thanks, Saml.

I decided to go with the ESP8266-01S rather than the full ESP8266 because my sensor require 5V power which I can get from the UNO, whereas the ESP only operates at 3.3V.