I'm curious if it is possible to program the arduino to control a set of LED lights to turn on and off at specific times of the day, but also use a motion sensor to control it at night when it is turned off. I'm pretty new at this so I am looking forward to see what i can do.
Yes, that's possible.
in general with a microcontroller you've got inputs (time-of-day & motion sensor in your case) and outputs (LED strips in your case). The input & output are "connected' with software.
The motion sensor is pretty simple so you might want to start with that. For your 1st development steps you can turn on & of the built-in LED with the sensor.
For time-of-day you'll need a [u]Real Time Clock Module[/u]. There are software libraries for communication between the RTC module and the Arduino so you don't have to write that code yourself.
Then, you'll probably want to add a clock display and some buttons so you can set the clock and on/off times. There are also libraries for LCD displays, but the display and user interface is probably the hardest part of your project.
Or, it should be possible to use your computer to set the clock and on-off times. That way, you wouldn't need a display or buttons, etc.
The Arduino by itself can only power a few "little" LEDs so you'll need a separate power supply and driver circuit to control the LED strips. RGB strips require 3 drivers if you want to control the colors separately. (There are addressable LED strips with build-in drivers and with those you just have to supply the power and a control signal directly from the Arduino.)
Yes! Why not start by defining the problem with specifications. What is the expected outcome. Purchase the Arduino cookbook and read it, this will give you some basics. also use the online tutorials and videos available, there are many good ones on this web site. At this point you will be able to define the problem and may have already solved it.