A specific meal of the day won’t affect your metabolism at all, so focus on eating a proper overall calorie/macro intake and work out hard in the gym, then you will be fine.
The quick guide to the daily amount of macronutrients you need is here:
Protein: Should be evenly eaten during the day, simply break up your daily intake into 4 or more meals. Before you ask, the body can use much more than 30 grams per meal so yes you are ok if you need to consume 50 or more grams per meal.
Carbs: Carbs need to eaten around the workout as they support recovery and help with performance. Simply create a four to five hour window around your workout and eat most of your carbs during that time frame. Let’s assume you train from 6 to 7 pm, you should start eating carbs around 3 pm and finish by 8 pm.
Fat: You should consume fat away from the workout as they slow down digestion. So if you are training late in the day, eat primary protein and fat meals early in the day or vice versa.
Meal timing before or after your workouts or any time of the day won’t affect your overall metabolism and your metabolism is only mostly affected by your overall calorie intake and overall macro intake.
The only thing that really impacts your metabolism to a certain level is the amount of food you eat per meal. Typically when you eat bigger meals, you boost your metabolism because your body knows that your are taking enough adequate nutrients for the body to be perfectly well feed. This will result in your body burning more energy. On the other hand, when you eat very little, your body will understand this and will slow your metabolism down to burn less and reserve nutrients for the future. So, eating a bigger meal can boost your metabolism but constantly eating big meals can result in fat storage.