I’m making a game and each level doesn’t even have that much to run so how do I make it run faster without deleting anything
Your question isn’t very specific but in general keep your draw calls down, use light mapping vs lights, combine your textures into a texture map, etc. Here are some links to get you started…
Graphics Performance
Script Performance
http://docs.unity3d.com/Documentation/ScriptReference/index.Performance_Optimization.html
General Optimization Tips
http://wiki.unity3d.com/index.php?title=General_Performance_Tips
First of all, delete all your Debug.Log(), Print() etc…
Second, profiler is your best friend. But? you doesn’t have one, so just try to comment half of your update, and compare. That way you can pinpoint your heavy functions. Things like FindObjectOfType() can be pretty consuming, so if you use them in update - stop doing that.