I am not very tallented in Computer , recenty I buy a acer laptop in this i can't able to connect the unsecure wirless net but one of my friend have a hp system in that we can easly connect the unsecure connection.
if have any adpter to connect this , if have pls tell
See your laptop's manual (instructions book) or the manufacturer's website to see if your model has wireless. It probably does have wireless if it's a recent model -- so have a look for a switch on the side or front of the case and turn the wireless ON.
If you are running Vista you should have no problem connecting to an unsecured wireless router that is within reliable range. With XP it should be quite easy if you just compare settings with your friend's HP laptop.