I need help doing a condition of a function and then a function out of that condition

Question

I need help, I've writen an code that randomly assigns an alliance to the user, then I wanted to do a condition that runs a function if the user gets a certain alliance, this means, if you get marine in the next line it appears a role from the marines, or if you get revolucionary army it appears a role from the revolucionary army. Note: This roles would also be random as the alliance.
This is my code:

function capFirst(string) {
    return string.charAt(0).toUpperCase() + string.slice(1);
    }

    function getRandomInt(min, max) {
        return Math.floor(Math.random() * (max - min)) + min;
    }

function alliance(){
      var alliance = ["Revolucionary Army","Marine","Pirate","Bounty Hunter","Cipher Pol","Royalist","Celestial Dragon"];

      var alliance = capFirst(alliance[getRandomInt(0, alliance.length + 1)]);
        document.getElementById("alliance").innerHTML = alliance;
    }


/* Rank */

     
if (true) {
    var alliance = 'Revolucionary Army';
    function rank(){
                var rank = ["Leader","Chief of Staff","Army Commander","Officer","Member","Associate"];

                var rank = capFirst(rank[getRandomInt(0, rank.length + 1)]);
                    document.getElementById("rank").innerHTML = rank;
            }
 } else {
   var alliance = 'Marine';
   function rankmarine(){
                var rank = ["Fleet Admiral","Admiral","Vice Admiral","Rear Admiral"];

                var rank = capFirst(rank[getRandomInt(0, rank.length + 1)]);
                    document.getElementById("rank").innerHTML = rank;
            }
 }

Answer 1

Make a function with the condition (if-else or switch) inside it. Like this

let alliance = "";

function capFirst(alli) {
    return alli.charAt(0).toUpperCase() +alli.slice(1);
}

function generateAlliance(){
      var alliances = ["Revolucionary Army","Marine","Pirate","Bounty Hunter","Cipher Pol","Royalist","Celestial Dragon"];

      alliance = capFirst(alliances[getRandomInt(0, alliance.length + 1)]);
      document.getElementById("alliance").innerHTML = alliance;
}

function getRandomInt(min, max) {
      return Math.floor(Math.random() * (max - min)) + min;
}


/* Rank */

function assignRank(){

 var ranks = [];
     
 if (alliance === "Revolucionary Army") {
     ranks = ["Leader","Chief of Staff", "Army", "Commander", "Officer", "Member", "Associate"];
  } else if(alliance === "Marine") {
     ranks = ["Fleet Admiral","Admiral","Vice Admiral","Rear Admiral"];
  }

  var rank = capFirst(ranks[getRandomInt(0, ranks.length + 1)]);
  document.getElementById("rank").innerHTML = rank;
}

link to fiddle: https://jsfiddle.net/wLoqejp5/