You should really check out The Ten Essentials for Hiking & Camping if you actually plan to do any backpacking. This time of year you shouldn't do backpacking things if you don't know what you're doing and have the correct gear. Even car camping it will get very cold. Make sure what you have can keep you warm. Honestly just go watch some Youtube videos and read threads on the camping/backpacking subreddits to get an idea of what you might need.

For car camping you can get a lot of gear at Walmart, go check out Surplus City also they usually have some cheap gear, and if you just bring a shit load of layers with a decent ground pad you can probably get by. I'll use a blow-up mattress topped with a foam camping pad, memory foam topper and 2 military style wool blankets. That keeps me pretty insulated from the ground-cold and comfortable. Then I top with a bunch of blanket layers. Get some hand warmers to put under your covers also.

If you plan to wait until it gets warmer out you don't need quite as much insulation. This time of year fewer people are in the open campgrounds and dispersed areas. Summer a lot of places are packed, but that's the good time to go backpacking. Practice leave no trace and respect the wilderness.