Here is your detailed meal plan:

**1. Lunch (51% of 2920 calories):**

Prawn Biryani
- Portion: 4.5 cups
- Calories: 1490
- Macronutrients: 45% carbohydrates, 30% protein, 25% fat

**2. Snack #2 (17% of 2920 calories):**

Chicken Mach
- Portion: 1 plate
- Calories: 497
- Macronutrients: 60% carbohydrates, 20% protein, 20% fat

**Grand Total:**

Day's total calories: 2920
- Fat: 24% (130g)
- Carbohydrates: 55% (394g)
- Proteins: 21% (150g)

Your grocery list for this meal plan should include the following items:
- Prawns
- Basmati rice
- Assorted spices and herbs for Biryani (coriander, cumin, turmeric, garam masala)
- Chicken
- Assorted ingredients for Chicken Mach (onion, garlic, ginger, tomatoes, spices)
- Assorted fruits and vegetables for added fibre and nutrients.

Please note that the portion sizes of the Prawn Biryani and Chicken Mach are just estimates and almost certainly need to change depending on the specific recipes used. This is just a general plan and adjustments might be needed to meet all guidelines precisely. Please adjust according to your tastes, availability of ingredients, and specific nutritional needs.