The choices we make in our past affect our future. Meaning, choices you made yesterday affect who you are today and choices you make today will affect who you are tomorrow. The structure of this quote is very eloquent (perhaps poetic) and formal sounding. It's not a casual/conversational statement, which is possibly why is sounds a bit strange the way it's constructed.

you grow to be the person you are. for example, let's say you do not speak Spanish today, but you decide you will start learning it today, you learn it, hard, and then there will come a day when you can speak Spanish.