You can apply for your PR as soon as you fulfil the requirements to apply under some immigration class, see http://www.cic.gc.ca/english/immigrate/index.asp
After you have lived in Canada as a PR for 3 years, you can apply for citizenship.
Most likely but if you find an immigration class you qualify under right now, say you qualify to apply under the skilled worker program for example, then you can apply right now.