要 meaning “need”

In much the same way as it can be used to express “want”, 要 can also express “need”. Have a look at these examples:

我要找到我的钥匙。

Wǒ yào zhǎodào wǒ de yàoshi.

I need to find my keys.

去美国要申请签证。

Qù Měiguó yào shēnqǐng qiānzhèng.

You need  to apply for a visa to go to America.

买汽车要花很多钱。

Mǎi qìchē yào huā hěnduō qián.

You have to spend a lot of money to buy a car.

In the above sentences, 要 could be swapped with 需要 (xūyào) without a great deal of difference.