It's perfectly okay to brush your teeth everyday using baking soda as a natural toothpaste.
But do be aware that using baking soda everyday to brush your teeth could cause you to wear off some of the enamel on your teeth because the baking soda is abrasive.
Some people don't have any issue with the enamel wearing off their teeth but some people do.
I would recommend just using baking soda to brush your teeth 2 or 3 times per week and then use regular toothpaste with fluoride the other times.
The fluoride will help keep your teeth strong whereas the baking soda will not although baking soda is a good natural toothpaste.