Can someone tell me if theres a website or software I can download that will tell me if a game will work on my laptop before I buy it

Games will normally state the requirements it takes to run the game. If you don't know your hardware spec's (IE: If you meet those requirements) you can check the game makers site (Some provide free tools to test your system for game compatibility) - or if you are on windows you can run system information tools (windows built in) to find your hardware information (Click Start > Settings > Control Panel >> System) - or you can search for "System Info (Sys Info) tool" at the links below this question to find software that may work for you.