Is tracking ovulation and periods reliable as birth control?

To start with I have very regular periods when not taking birth control. but I have had to take birth control recently because I don’t want another baby but it makes me so nauseous and I have a lot of intermittent bleeding and it just really effects me badly. I want to stop taking my birth control and just keep track of my periods and ovulation to prevent pregnancy but I’m not sure this is even reliable. anyone done this method successfully? If not, any better options for birth control than the pill? The truth is I’m just not good at taking the pills but I DONT want another baby