Hello Veronica, firstly you need to gather as much information as possible about the position. For sure you can find information about it by asking your HR person or your direct boss. You need to know which are your responsabilities, what you need to to, whom to contact when you need help and advice.
From my experience I can say that in order to gain experience you need to be curious and brave. Don't be afraid to ask as much questions as you can and if you dont understand something from the beginning, ask over and over again. Everybody had a first job and started from scratch. If you dont get an asnwer, dont feel dissapointed. Kepp it in mind and keep asking it until you get the answer you want or you understand the situation. For sure, everybody will explain you stuff on "their language", with terms that you dont understand or never heard about. But again, don't feel discouraged. Ask your colleagues that have more experience and try to explain them that you dont feel very confortable with their language.
Another important thing is that you can and may watch your colleagues on how they act, how they dress and how they speak. If you ever feel that something is wrong, try to follow your instinct. If you dont like it, dont do it. It is very important to follow your values and respect them.
Being a freshman in the company, try not to be late in the office, get in time and respect the schedule. Eventough you see that all your colleagues get late in the work, try to do your best.
And the last but not the least, be curious, curious and curious!!!