It’s normal to have questions and be curious about sex and it’s also normal to not want to think about it because you have many other more important things on your mind. The answer to your question is this: Condoms usually don’t break if they are stored and used correctly with space left at the tip. If a condom breaks, it has been exposed to high temperatures or direct sunlight or it has been torn by teeth or fingernails.
Condoms protect against most (but not all) sexually transmitted infections and they can lessen the chance of pregnancy however, it is best to use two forms of contraception (such as the Pill). If a condom breaks and you are not using a second method the semen which carries millions of sperm can spill into the vagina making it possible to become pregnant. So it is important to use Emergency contraception such as Plan B or Ella. If your partner has a sexually transmitted disease, and the condom breaks, you are also at risk of getting whatever STI your partner has.
Your best bet is to talk with your health care provider and also read about different birth control options and whether abstinence is best for you. Before you become sexually active with anyone, ask them about their sexual history, such as whether they have ever had unprotected sex. Get tested for STIs (if you or your partner have been sexually active) before you have sex and then use a reliable method of birth control along with condoms every time you have sex after that.