Lets say i have an arcade and for every page i want different keywords that i'm going to put in the meta tag,for example if i have a halloween game i will put "games,halloween".My question is what other keywords i can use for games,the more general ones.
Forget meta tag... SORT OF. Although it might help, stick to content (hint: focus on the description) (second hint: wrap your php include of description with section targeting). Goodluck.
You want arcade keywords? Games, Flash Games, Online Gaming, Xbox, Playstation, Wii, Nintendo, Mario, Tarzan Games, Arcade, Arcadeing, Fun Games, Free Games, Flash Gaming, Miniclip Games, Free Arcade, Penny Games, Arcade Videos, Game Videos, Play Games, Online Game Play, Arcade Downloads, Game Downloads, Flash Arcade, Arcade Flash, Xbox Live, Xbox 360, Halo... the list can go on for ages...
i was thinking about more general keywords for adsense,not for seo,can i put entertainment,fun,relaxation?
Just make sure not to use unrelated keywords on the site. Some people start keyword stuffing with unrelated keywords to the sites content and get banned from AdSense. As for the keywords you mentioned--entertainment, fun, relaxation--if it's related to your content, the AdSense ads should have already picked them up. Just make sure not to try and manipulate the ads.
look at google adword for free keyword....(basic knowledge) https://adwords.google.com/select/KeywordToolExternal?defaultView=2