i need to turn the led on for aproximately 1 second then off, then on for 2 seconds then off and not have it repeat.
I'm not sure I understand... If it doesn't repeat, how can it be off for only one second? ...It's off "forever" (or until triggered), on for 2 seconds, and then off "forever" again.
Or, is that a delay? i.e. It's off and you trigger it... One second later it comes on for two more seconds? For that, I think you'd need two 555 timers (or a 556, which as two 555s built into one package). You might also need a couple of "logic chips" (and-gates, or-gates, flip-flops). ...No, I think it can be done with one timer and some logic, but I can't design it in my head.
I assume you learned enough from your digital class to do that... It should be really "simple", but not as simple as copying an example sketch, if you are a beginner in electronics & programming.
- R-C time constants are not as accurate as the crystal oscillator in a microcontroller. So for example, if you are blinking once per second, and it's really important to blink exactly 3600 times in one hour, an R-C oscillator won't cut-it. You can use a cristal oscillator with simple logic circuits (instead of something like a 555), but they don't come in "slow", so you need a divider (more logic circuitry) if you're going to use a megahertz crystal to blink an LED at 1 Hz.
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i need the circuit to stay off permanently until its activated manually with a button, when i press the button i want it to turn on for 1 second, off for one second, on for 2 seconds then turn off and remain off until the button is pressed again. does that make it more clear?