Amigas don't have much bandwidth so your network, wireless or otherwise will pretty much be limited to around 10Mbps. Adding WEP encryption will slow it down some more.
He won't see speeds much over 3Mb/s (400KB/s) on a PCMCIA wireless card on the Amiga.
@AAACHIPSET -
First you should add CardReset, found at
http://aminet.net/package/util/boot/CardResetThen you need to add your SSID and WEP/WPA key to your Startup-sequence (if you got no clue what this is ods are you haven't changed them and you will find them on a label on the modem/router.
So after you added CardReset you should edit your startup-sequence and near the end right before C:LoadWB you should add the following lines
C:CardReset TICKS 50
C:SetPrism2Defaults SSID "YOUR SSID HERE" KEY "your WEP/WAP key here"
Remove the quotes and write there then just save and restart. Done.