How do i make the boat move according to what the player rolls and how do i scatter the traps?

I'm relatively new to programming and I have an activity where I need to create a boat racing game. In the game the player needs to move forward or backwards based on the roll of a dice. There are traps (#) and currents (C) in the game which need to be randomly scattered across a 100 column track. I'm having trouble getting the player to move as well as the traps and current to be scattered randomly. I know for the traps and current a random number generator is involved but I'm confused on how to use it. Can anyone help if it's not too much trouble? Here is what I have so far:

package boat_race;
import java.util.Random;

public class River {
    public int[][] river = new int[2][99];//[1]
    int freq;
    int position;
    int count = 0;
    Random scatter = new Random();

    public void setObstacle() {
        //scatters both current and trap

        for(int count = 0; count<40; count++)
            {freq=scatter.nextInt(40);//frequency
                position=scatter.nextInt(99);//position on the array

                river[0][position]=freq;
                //river[0][position]=5;
                river[1][position]=freq;
            }

    }
    public void checkObj(){
        while(true){
            if(river[0][count]%2==00){
                //even number and moving back
                count++;
            }
            if(river[0][count]%2==1){
                //odd number and moving the number
                count++;
            }
        }
    }
    public static void moveP1() {
        // TODO Auto-generated method stub
        
    }
    public static void moveP2() {
        // TODO Auto-generated method stub
        
    }
    public static void scatter() {
        // TODO Auto-generated method stub
        
    }
    public void winner() {
        // TODO Auto-generated method stub
        
    }
}