Internet is dead.

Better list?
1: make sure wifi card is there first. or all this is a waste, ok?
2: reboot modem. if all devices in home using wifi are dead.
3: reboot router, if not part of modem above, for same reasons.
4:use Ethernet wired first. get that working first so you can connect to the internet and get drivers missing for you wifi card, inside.
now that internet works we may see XP actually find drivers automatically, using its PnP engine, but XP is dead, now at Microsoft dot com. dead as door nail. but hope springs eternal for XP (not)
The Device manager must show the wifi card is present and
not bleeding red errors, yellow errors or listed UNKNOWN.
IF is bad there, then the driver is missing bad corrupted or the wrong one loaded.
finding xp driver 99% of the time nets you a virus
most sites that say free drivers are malware sites feeding off the bones of the last few XP users on earth. (sad to watch)
I do have safe drivers. they are here. (I do not work there)
but takes skill to use. (I download them)
then I use virustotal.com on the package, it is clean !
ask for help or post the photo of you wifi card so I can read the sticker and tell you what you have and what drivers are possible.

here is the one known safe site for such relics. WLAN.
version 12 should have your driver but is stored in torrent free site.
as you can see there are vast wifi chips used.
that is why I use DM (properties IDs) to find the true name.

http://driverpacks.net/driverpacks/windows/xp/x86/wlan



there are 3 ways to ID the wifi card
1: read is label sticker (eyeballs do not lie)
2; use DM and details tab above.
3: run HWinfo32.exe portable, (free ) run it and it tells you if wifi is there and what chips it is, maker of chip and model.#

And after all that then maybe the wireless card is shot.