Wireless internet connection. When I first purchased my computer, I was able to go anywhere that

Question

When I first purchased my computer, I was able to go anywhere that had wireless internet and I was able to connect with no problem. Now, I am not able to search for wireless internet connections or connect in any area where there is wireless internet. Is there somewhere i can go on my computer to turn something back on or what else could be going on. I have DSL at my home but it is not wireless. Gateway MX6445 Laptop

Thank You