Answer 1

a , b
//where a>b
int x=(new Random()).nextInt(a-b+1)+b;
//note ::: considering between includes extreme values also ☺

Answer 2

import java.util.Random;
public class Program
{
public static void main(String[] args) {
Random r = new Random();
int x = 2 + r.nextInt(2);
System.out.println(x);
}
}

This is how!
2 + nextInt(2)... will choose between 0 or 1 randomly (i.e., max 2 numbers starting from 0). Then you're adding 2 to whatever number system chooses. If it chooses 0 becomes 2, and if 1 then it'll become 3.
Thus results in 2 or 3 as output.