You will be able to speak a foreign language even if you don't go overseas to study it.
Nowadays, you can study foreign languages in your country. If you meet the person who says '' I'm jealous of you. You can speak a foreign language because you had studied abroad for 1 year. I don't have enough money to do it.'', you should think that it's an excuse. Even if you live in your own country, you can still talk to native speakers on Skype. The question is why people go to other countries to study languages and spend so much money. In my opinion, the answers are that they can learn other cultures and make international friends. If you think you have to go to other country to just study foreign language, you should change the way of thinking about it. I'm sorry I'm a little insane. Some people might feel uncomfortable.
Great job! I made a few small corrections.
I think it is still useful to go overseas and study because you are forced to use the language to survive. For example, if you go to America to study abroad and you only speak Japanese, you will have a hard time getting some things done. Thus, you are forced to speak English and plus you will have many more oppotunities to speak it too.