I recently got a Cannondale Slate and because I’m a complete novice, I’m a little hesitant in starting to ride on trails alone. I’m mostly wondering if I’d have to perform many jumps (which I don’t know how to perform) on the trail. Any advice on trails or best practices would be highly appreciated.
Welcome to the Bay Area! First, you should become a member of Bike East Bay - they provide advocacy as well as produce bike trail maps for the east bay. Being a member gets you a discount at most east bay bike stores.
Second, the gravel trails around here are all fairly gentle in terms of terrain except for some steep hills. You could do them all with a hybrid if you're fit enough. So my advice would be to just find some trails - either along the coastline where it's flat - or in the hills where you get the view -- and just do it.
The best way to learn is to just ride! If things get sketchy just take it slow. There are group rides scheduled through Bike East Bay, REI, and other organizations. Check through them or places like Meetup.
PS: You can find some very difficult, double black diamond trails for mountain biking in the east bay but you'd really have to go out of your way to look for them. Marked trails on the bike trail maps (and on google maps) are all beginner level.
Gravel riding does not have to involve getting over 'technical' obstacles on the bike, although even on straightforward trails you may find you have to carry the bike over obstacles such as mud, steps or stream crossings.
It's good to ride with others to get to know trails and techniques and have some technical backup, plus it's just good to ride with friends; but you tend to meet people to ride with and make friends on the trail. Organized group rides are a great way to get started.
To get started on you own, research trails near you and select something that suits you in terms of surface, length, and amount and difficultly of climbing and descending. If in doubt start on the easy stuff and work your way up.
When going out on a ride, on your own or with a group:
Check weather and dress appropriately, including applying sunscreen.
For longer rides, make sure you have plenty of daylight to complete the ride.
Take a few essential tools. For short rides near civilization: a multi-tool and a puncture repair kit or spare tube are fine. Obviously you'll want to know how to repair a puncture and make at least basic adjustment to your bike.
Make sure your tires are inflated to an appropriate pressure for the surface you are riding on (higher for paved, lower for gravel or loose). The tire's pressure range is written on its sidewall, or consult your bike's owners manual or tire manufactures website.
Bring sufficient water (or know where to top up), energy bars or snacks.
Bring a (charged) mobile phone for navigation or calling for assistance in case of bike failure or injury. Bring a backup paper map folded in a sandwich bag so it does not get wet from rain or sweat. (Putting you phone in a bag protects it from moisture too.) If you research trails online they often have maps you can print, or print from Google Maps with the bicycling option turned on. Highlight your route or add hand written annotations if you want.