What are some advices or tips for first time homebuyer approved for low income family CAL-HFA or FHA loans?

I live in California. I heard there are ways to get the government to reduce your property taxes, get the seller to pay for your closing costs, get a down payment loan with no interests, and many more (feel free to fill me in). My family qualifies for CAL-HFA or FHA loans because we are a low income family, we plan to borrow a couple thousands from different relatives but aside from family help, what can we do to utilize the government's help or programs to the fullest? Any tips or advices or new discoveries that I don't know of are welcomed. My dad has excellent credit by the way. Thank you and I greatly appreciate it.