Hi! Replying in case you are still feeling stuck.
The fire starter tool can sometimes seem like it's not working, but it can take a long time for things to light. Make sure to hold down shift and be patient. You can't eat the roots without cooking them first, unfortunately. You'll need to collect more wood in the day time. Berries, mushrooms, and wild crops are good first food sources.
That first night can feel really long. If you can collect 24 pieces of grass with a flint knife, you can make a bed to pass the time. Early in a play through, I generally spend nights clay forming or sleeping. You can also make it so that opening the handbook doesn't pause the game, so when I was a newbie player, I spent a lot of time reading in the night time.
I advise you find a grassy place adjacent to a forest so you have open space and access to food. Don't settle in a gravel/sand biome. Take your time learning mechanics and enjoy the early game. The struggle is a big part of the fun, but if you feel it's too hard, don't feel bad starting a new world and adjusting some settings to have a softer start.
Feel free to ask more questions. Good luck.