header file question

If I was to make a new header file(.h) and include every library in it to easily include them in my program, would it make it very large?

libraries are linked into at compile time... if what you meant was that you'd include all other headers... then yes, you would have a very large exe... but if you only do the ones you want for organization, that's a good practice... and if you did link to all libraries, you'd surely get a large executable... also, when you include particular headers, you are automatically linked to the appropriate libraries...