The short answer is yes. You can’t control everything about yourself though (unconscious stuff). And you can’t start controlling all of your behaviour in one day.
We are habitual. What was your routine this morning? Compare it to your routine yesterday – you’ll probably notice similarities. Behaviours are habits, and so are thought patterns. For example, sometimes I see a stranger in public, compare myself to them, and feel bad about myself. This is a habit I’ve created for myself. And in order to start controlling myself, I have to consciously stop habits. It’s not easy, just like it’s not easy to stop smoking.
Your brain is on autopilot for a big chunk of the day. To break out of your patterns, you have to first practice self-control. Things like journal writing or talking with a close friends have helped me. Label your habits, and start to understand what’s wrong with them. Ask yourself: why do you want to stop these habits?
There are some apps that can help with becoming more self-aware of small habits and help you set attainable goals to overcome or replace them. Don’t expect to replace a habit in a week. Our biology is habitual so we can become efficient creatures. So, we have to work to break this efficiency.
So, yes, you can mostly control yourself. It just takes conscious awareness of actions and a bit of energy.