to have
In French, 'avoir' is used to indicate possession, quite similar to 'to have' in English. It is also used in a variety of idiomatic expressions and in the formation of many compound tenses.
I have a black cat
In French, 'avoir' means 'to have'. The phrase 'J'ai un chat noir' translates to 'I have a black cat'. Here, 'avoir' is used in the standard context of possessing something.
We need help
In French, 'avoir besoin de' means 'to need'. So, 'Nous avons besoin d'aide' translates to 'We need help'. Here, 'avoir' is used in conjunction with 'besoin' to convey necessity.
You have beautiful eyes
In French, 'avoir' is used to describe physical attributes. 'Tu as de beaux yeux' is a compliment that translates into English as 'You have beautiful eyes'.