indoor garden

Sounds like you need to do some basic research before proceeding.
Arduino links.

Watch these:

Some things to read:

https://learn.adafruit.com/category/learn-arduino

https://learn.sparkfun.com/tutorials/tags/arduino?page=all

https://learn.sparkfun.com/tutorials/what-is-an-arduino

http://playground.arduino.cc/Code/AvoidDelay

https://forum.arduino.cc/index.php?topic=384198.0

https://learn.sparkfun.com/tutorials/using-the-logic-level-converter

http://arduino-info.wikispaces.com/

https://learn.sparkfun.com/tutorials/how-to-read-a-schematic

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