You need to start with a circle, a square and a triangle. 

Start by learning to search these forums. This question comes up a lot.

Out of curiosity: How old are you? The advice for a high school student is going to be very different from the advice for a 30 year old.

Invent a time machine and go back to when you did have the time and enrol in a architecture school.

Are you thinking architecture practice or architecture studies? Find a firm nearby, make an appointment to 'job shadow' and see if its what you are interested in as a rough idea. Write down a list of questions you have and take that with you. Architecture education and practice is going to vary greatly among countries but I can't imagine many places offering online degrees. The education and training process is long and continuously changing. On another note, you may find it easier to do an architectural technology path. Since this is more of a technology route a lot of times its offered online and in about 2 years vs a 4+ design degree. 

Learn enough CAD and BIM to get you a job as an entry-level drafter. Learn everything else on the job.

Learn to sketch, visit building sites and finished buildings, draw what you see and what you don’t see. And for the all the software >>>youtube