Confused?..............?

lets say,what if you dont know what is the length of your cycle. and you never track your cycle ever.is it still possible for you to conceive immediately? and to know when did you ovulate even not knowing important things like the length of your cycle? is it really exact to estimate that the ovulation day of women are mostly 14 days counting from the first day of your LMP? THEN,after you had unprotected ,how many days really exactly are you to become pregnant? when will fertilization takes place? conception? and also implantation?..thank you all...