Brief Answer:
Quality proteins should be taken.

Detailed Answer:
Hi Sir

Thank you for asking ask a doctor service.

I have gone through your query with diligence. For working out in gym you should take proper quality proteins, healthy fats and carbohydrates.
You can have light foods like bananas for pre workout not to get exhausted. After work out also banana is good which gives potassium and energy for your muscles. You should take food within 2 hours after work out.
You can take 150 to 200 grams of chicken or fish or beef. If you don't like that then 10 egg whites will be enough to serve adequate protein. While taking 10 egg white you can take 2 yolk for fat. You should also take good carbohydrates like brown rice. Brown rice also you can take 150 to 200 grams. Post work out you can also take yogurt.
Supplements which contains BCAAs - leucine isoleucine and valine amino acids can be taken. This will help you to get good muscle mass. These are muscle friendly amino acids. This will decrease fatigue and soreness also.
Avoid steroids and diuretics. You should also drink proper amount of water. Avoid excess sugary drinks.
BCAAs you can 200mg per body weight. That is if you have 75 kg then you can take 15 grams. Other supplements like whey protein also you can take. 1 to 2 scoops will be enough that is 25 to 50 grams after work out.
Make your break fast and luch as the main ones and others light ones.
Let me know if anything not clear.
I am happy to help.
Thanks.

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