i have Half Life how do i update? pls help if anyone can.thankyou

Half-life 1 or 2?

If you bought it then you need to Download steam and put the game into Steam, It will update the games since Steam was made by Valve ( Creators of Half-life )

If you bought the game off of steam then you should have the Latest update for the game, if not then try Right Clicking the name of the game and click View Update News and see if there were any recent updates

Hope I helped :)