You cannot have multiple draw() functions, but you can change the code that gets executed on a frame-to-frame basis. In many applications, there are different states that the application can be in - e.g. a Menu state and a Game state. The most common way to change between these states is to use a global int variable (e.g. state) and a switch statement in draw(). If you are more advanced, you can define constants that map a variable name to a value. For example:

1. int state;
2. final int MENU = 0; //The Menu state, also the default
3. final int GAME = 1; //The Game state
4. 
   
5. void setup() {
6.   //Blah blah blah
   
7. }
8. 
   
9. void draw() {
10.   switch(state) {
11.   case MENU: //The same as "case 2:"
    
12.    
    
13.     //Blah blah blah
    
14.    
    
15.     break;
    
16.   case GAME: //The same as "case 1:"
    
17.    
    
18.     //Blah blah blah
    
19.    
    
20.     break;
21.   }
22. }