1 opening for white and 2 for black

can you get by only knowin one opening for and two for black? i always start off the same was as white (the bird) and when im black i play i have 2 opening (dont know what they are called) i use depending on what white does first. should i exspand my opening repretoire or just get really good with the ones i use now? 

As long as you feel comfortable in the opening and it is sound, you can use it forever. If you like Bird's opening you may want to give the Dutch defense a try. I don't think any decent defenses with an early f pawn push exist against 1.e4

Stick with what you're playing for 1-2 years until you become confortable with the middle-game themes.  If you like the Bird's play the Dutch against Q-side openings and the French against the Kpawn games.

i looked turns out ihave been using dutch and the other i use is Nc6,g6,Bg5,Nf6 dont know what that one is called

I would call your black defense a Modern.

The 3 opening strategy does work for beginners, it will get you up to a reasonable club level. Then you need to expand your repetoire.

I 1st saw this system in the book "How to Think Ahead Chess" by Horowitz & Reinfield, its still around if you want to check it out.

Hmmmm, I can see why he uses an engine, obviously lacks the intelligence to play without one!!