Have been using UNO MEGA for small projects. Recently bought an UNO for other projects. Can I just go into the IDE an under Tools select UNO and a different port to do projects and rename sketches to keep track of sketches. Do not wish to use boards at the same time.
That's the way to do it.
You need to select the type of board first:
And then the port. You can have both devices connected at the time and select which one you want to program.
With Arduino you can do OTA (Over The Air uploads) to NodeMCU and other ESP8266 based systems.
If you want to run two instances of the IDE, to work with two different boards at the same time, use UECIDE.