If you are moving out of your family’s home and into a rented room of your own, you will encounter practical differences and emotional differences (and some that are both). The responses above have done a nice job with the practical differences. Here are a couple of emotional ones.
1. You are going from living among the people who care most about you in the world to a place where there will not be anyone who notices when you come and go and where no one will care if you don’t show up for days.
(This does not apply if you are going to a dormitory room or school housing, where someone acting in loco parentis is supposed to keep an eye on you.)
2. You are going from a place where you may have taken certain things for granted—shared chores, home-cooked meals, a normal household’s supply of tools and materials and seasonal items and so on—to a place where basically nothing is provided but what you bring and there is no one on hand to rescue you.
These are a drastic changes. They are both scary and exhilarating. Don’t be alarmed by them. Just be aware of them. You are responsible for yourself now.
Taking care of yourself will build muscles you don’t yet have. They get stronger with practice. It is very important to gain those strengths for your life. Keep your head, use your good sense, and learn from your experiences.
And one practical thing:
Have your key in your hand when you go out the door. And carry a spare.
[Edit] This response was written before the completion of the above post explaining your living situation.