You can't just grow and sell without going through the system. It's complicated and costs money. You can bypass that but I doubt any clubs are going to risk buying from someone that isn't licensed with the state. And then if you do get licensed there is no guarantee that they'll buy anything from you. The seed to sell supply chain is pretty much sewn up already. If you have to ask how to sell and how much they pay then you're already out of the loop and chances are you would not even be able to join the crowd. Sure you could get a license to grow but finding legal buyers for your weed is an entirely different thing.
Many people think because they grow decent weed that people will buy it from them. That may be the case in some states but Oregon and California have some tight knit groups and you are not likely to become part of them as they don't really like or need outsiders.
I'm posting a link that outlines the steps you need to take to get a cultivators license in California. It's a rather drawn out process and will end up costing you thousands of dollars. You don't just pay $500, grow your weed, walk into a club or dispensary with your weed, and walk out with money. Chances are they'll tell you to go away since they already have all the suppliers they need. You're late to the party. If you're looking to make some extra money you'd be better off driving for Uber after work.
Cannabis Cultivation License Application Overview
https://static.cdfa.ca.gov/MCCP/document/2017 1228 Licensing Workshop Presentation.pdf
Just some of the requirements:
Apply for one of several cultivators licenses
Pay annual license application fee
Pay annual license fee
Pass a criminal background check
Obtain a valid seller's permit number
Provide a deed to the property where it will be grown
Post a surety bond
A property diagram
And a hell of a lot more steps to take. Read the link above.