Working for the first time and first day

My first day of work i was like looking so blur and don't know how my job scope would be.After i knew about my job scope i was thinking of how lucky am i getting this job.I din't know that i have so many things to do and it all involving keying data which invove alot of step and it even make me more confuse and even more blurry now.I hope i can observe whatever that i have learn and not to make the situation worse. Day after day passed by i was thinking of resign for my job.Today is only the 3rd day of my working and i'm streming and complaning .How am i going to continue with my job after this. I need a helping hands sonner as possible.