Natural birth control, no condoms?

I am thinking about getting g off my birth control for many reasons.However, I just have a few questions. What ways (apps,thermometers, ovulation tests, etc.) help you track your cycle and prevent pregnancy’s? Also do you use condoms or only when you ovulate? I am currently not using condoms and was wondering if I could just use them during my fertile window? I have only been on birth control for around 9 months now.