Ther is one standard called the wingspan method. You stand with your back against a wall with arms outstretched to the sides. Mark the wall where your fingertips reach. Measure this, subtract 15", and divide what's left by 2. Personally I found this to be a bit short for be, but it's a good place to start.
The method I like is to measure your wingspan and divide by 2.5 This seems to work better for me as the other way just seems too short for me.
At least you'll have a decent place to start. Consider that once you learn something about shooting form and start noticing you'll see that fully 75% to 80% of shooters are shooting bows that are 1" to 3" too long for them. It's much easier to shoot accurately with a bow slightly shorter than slightly longer.
As for bow weight? You can shoot as much weight as you can handle accurately. Good way to gauge this is to sit on the floor with your legs out in front of you. Hold the bow out level as if you were going to draw it and then draw it straight back. No reaching for the sky. If you can, for example, pull 50 lbs this way then you can figure you should buy a bow with about a range from 50 to 60 lbs. Your muscles will improve over time and you get stronger, so you can cracnk some weight on. But also consider that almost any modern compound bow of about 60 lbs is capable of killing any animal on this continent, so down't overbow yourself. This is not a macho sport. Keep this last statement in mind. Accuracy is what matters.