Plug your iPad into your computer and start iTunes. On the left side of iTunes your iPad will be listed about midway down. Click it. In the main screen window of iTunes it will show a picture of your iPad. Below that picture is a button that says "check for update." it will tell you if you are on the current version.
That being said, why not do some research on these forums and online and learn about your iPad. The "search" button is your friend.
You will need to plug it into a computer and open iTunes. Then click on the iPad in the left hand bar. Then the iPads settings will come up. Right click the iPad and chose Backup. Then right click and chose Transfer Purchases. If you don't have your music in iTunes - I suggest first pulling it all off via a third party program like tansee iPad transfer. If you already sync to iTunes anyways or don't have any video/music disregard that step.
Once you have all your purchased music in iTunes and have completed the backup, Click iPad and then click Update towards the middle of the right pane. It will update your software now.