|Apparently you have a Dell Inspiron laptop. |
If you got it new, it may have come with a Dell Drivers and Applications CD, or similar.
If it did, the drivers are on that.
If you don't have that or have misplaced that....
IF the country you bought the computer in is not the US, change the country top left.
Select Support for Home Users - Start here
Click on Drivers and Downloads
select Choose by Service Tag if you can still read it - that's on the label on the bottom of the laptop.
Otherwise select by model - however, I don't see 1505 there, on the US or UK sites. If you didn't make a typo, try 1501, 15xx, etc.
When it finds your drivers and downloads, make sure the right operating system is correct, click on Network.
You can download just the wireless adapter "drivers", download the other ones listed there later, but you should download at least the wired network adapter "drivers" too, because it's much easier to connect to the internet via a wired network adapter and a network cable, and you may need to connect to the router as well via a network cable so you can look at it's configuration settings.