Hi Eyeluvyeww,
Welcome to Second Life!
You can either find a job inworld and earn Linden dollars (L$), or you can buy Lindens. In order to buy Lindens, you will need to go into your Account>Billing Information and add a credit card or PayPal information. Then you can either buy L$ from your account page on the SL website or your avatar can buy them inworld. One US Dollar ($1.00) will buy about L$250.
Here's a link to a helpful article:
http://community.secondlife.com/t5/English-Knowledge-Base/Buying-and-selling-Linden-dollars/ta-p/700107
Good luck!