Easy Vegetarian Broccoli Chowder

Name: Easy Vegetarian Broccoli Chowder
Ingredients: 4 cup Broccoli ( cut into small florets); 1.5-2 cup Sweet potatoes ( cut into cubes); 1 cup celery (- 2 sticks chopped finely); 1 small Banana Wax Pepper (- or Green pepper, chopped (Optional)); 1 Onion (-small, chopped finely); 2 garlic cloves (- medium size garlic, minced or grated); 4 cup Water; 3 cup Milk; 1 tablespoon Whole Wheat Flour (- Optional, can be replaced with plain flour/ All purpose flour); 1/4 cup Milk (- Optional); Salt (- to taste); Black Pepper (- to taste); 2 tablespoon Butter ( - Can be replaced with vegetable oil)