The California Department of Parks and Recreation is popularly known as the State Park System. Within the system you will find almost 15,000 campsites spread across almost a million and a half acres in 278 different locations. The kinds of campsites vary from beachfront spots to pitch a tent to mountain sites with full amenities. Fishing in the state parks ranges from ocean catch to freshwater angling. You can make reservations for camping from its website, where you can also find all the information you need to plan a trip.
You can fish along much of the Pacific coastline of California. Beaches are managed by various organizations. Some beach areas are managed locally by cities or counties. For example, in Los Angeles the beaches are managed by the county of Los Angeles. In other areas the beaches are within a state park, such as Sonoma State Park in Northern California. Each area determines if you can camp at the beach or not, so make sure to check. The California Department of Fish and Wildlife offers a guide on beach fishing the large variety of species on the coastline.
Although the United States National Park Service (NPS) has over 30 locations in California, when it comes to fishing and camping, the number diminishes. Many national parks in California are historic locations rather than recreational areas. The upside is that NPS has some famous and spectacular fishing and camping locations in California. Yosemite National Park in the Sierra Nevadas draws campers and anglers year-round. Point Reyes in the San Francisco Bay Area offers camping and fishing with some sites accessible only by canoe. You will need to make reservations for some campsites.
Throughout California you will find smaller lakes designated for fishing. Some are managed by counties or local municipalities, while others are privately owned and may charge a fee to the public. These locations seldom offer camping, but commercial camp locations are frequently nearby. In Southern California you can find trout lakes in Orange County and the Low Sierras. In Northern California, the Sacramento River Delta is a popular location for fishing. Make sure to consult the Department of Fishing and Wildlife for details on fishing licenses.