Condoms are always a good choice for sex (no matter how many times you have or haven't done it) because they are the only contraceptive choice that also provides STI protection. Even if one has not been sexually active in the past or refers to themselves as a "virgin" (which can have a TON of meanings), that is no complete guarantee that you'll be STI free, so using protection and getting tested regularly is still a necessity. They are also nice because they are inexpensive, relatively easy to find/purchase, and only need to be used when you want to be sexually active (in contrast to something like hormonal contraceptives, which must be taken/used all the time to be effective). Condoms are also highly effective when they are used correctly and for all genital contact.
There are other contraceptive choices available to you if you would like. Hormonal methods (like the pill, patch, ring, or injection) are favorites of some women because they are something you can control and know that you are taking. However, they don't provide STI protection and hormonal methods aren't the best for everyone as they can have some side effects and must be taken regularly and correctly if you want them to work. They also require a prescription to obtain. You also have options like a diaphram or Lea's Shield which are used with spermicide. While these are non-hormonal and are used only around the time you are having sex, you do need to use spermicide with them (which isn't a hot idea for everyone as that can be irritating and can increase the risk of STI infection) nor do they provide STI protection. Again, they also require a prescription. I'll link you to our article about birth control options so that you can get a good idea of all of the options available. If you are concerned about pregnancy and want to reduce your risk further, you may wish to double-up your methods. By using two methods, you further reduce your pregnancy risk because you have a backup for your condoms should one break or slip. Note that this does NOT mean using two condoms at once, that actually increases your risk of breakage. But you may wish to use something like the pill (for example) to backup your condoms. Backing up your condoms provides you with about the most protection possible (outside abstaining completely). You may also wish to ensure that you have access to emergency contraception ("EC," "the morning after pill," "MAP") in case of a condom failure.
You may want to check out the following articles:
Ready or Not? The Scarleteen Sex Readiness Checklist
Safe, Sound & Sexy: A Safer Sex How-To
Margaret Sanger's Disneyland: Choosing Contraceptives
Condom Basics: A User's Manual
Your Map to the Condom Aisle
Advice: What's THE BEST condom?
STI Risk Assessment: The Cliff's Notes
What's the Risk? Easy Pregnancy Risk Assessments