Architectural or civil engineering

Hi Sydney! 
My name is Deborah Suazo and I'm a Civil Engineer. I so glad that you are already interested in engineering and that you want to start preparing yourself for the Future. 
To answer your questions:
How I can prepare for a career in engineering:
First, you got to do good in school. Push yourself to be good in Math and Science, be the best in your class if you can. Why I tell you this? Because Engineering revolves around math and science, engineering is bringing math and science to reality. Why be the best? Because if you are the best you will be able to get to a great school with probably a Honors Scholarship.
If you could while in High School, look for an Pre-Engineering Summer Camp. I did it while I was in High School and it really gave me a direction.
http://www.collegexpress.com/lists/list/pre-college-engineering-summer-programs/1842/ 

What is a normal day in civil engineering?
Well, we do alot of field work supervision. Meaning, we probably checking that the construction its been done according to the plans, specification and laws. Also, we do inspections, maintenance and repairs. Of course we don't tend to go Home Depot and do the repairs ourselves but we do know what needs to be done, how much it cost, who to hire and where we can get the best materials for the job, this  is call Project Management. There are some that focus in designing. Designing roads, bridges, building, etc. 
I really dont know in detail what does a Architectural Engineer do, but I do know that in school you take most of your courses in Architecture with Structural Engineering classes. 
I hope this can help you! If you have any more questions feel free to contact me.

Glad to help!
D.Suazo