hello im ashrobhoy i can help you with questions

Q my map has a leak how to FIX
A click map on the option abr on hammer then lick load lin file and then a red line apperes follow the line and it should go outside the map cover the hole and its fixed

Q HOW do i make maps
A use sorce sdk in tools on steam on the options put sorce engine 2009 and choose portal if its for portal then click hammer at the top

Q How do i take a look at maps other people have made so i know how to make one
A use vmex turns the bsp in to a vmf ( hammer map edit file) but you should ask the original creator if you are going to reised an edited version

Q how do i make a bonus map file bzm
A dont know

Q how do i do this that on hammer
A called google very helpful

ask anymore questions and someon tell me how to make a BZM bonus map file please