I usually eat a banana about 30 minutes before going to the gym because it gives me quick energy and helps me feel ready for my workout without making my stomach feel too heavy.
If you want more energy before the gym I would suggest eating something rich in carbohydrates such as oats rice toast or a banana because carbohydrates are one of the main fuel sources your body uses during exercise.
You do not always need an expensive pre workout supplement to improve your stamina because a balanced diet proper hydration and enough sleep can make a noticeable difference in how you feel during exercise.
Water is one of the most important things to consider before the gym because even mild dehydration can make exercise feel harder and may affect your performance especially when you sweat a lot during training.
I would recommend eating a proper meal two to three hours before your workout if your schedule allows it because having enough time to digest your food can help you avoid feeling hungry or uncomfortable while exercising.
Sometimes the reason you feel weak during a workout is not that you need a supplement but that you have not eaten enough throughout the day so make sure your regular meals provide enough calories and nutrients for your training needs.
A banana with some yogurt can be a convenient pre workout snack because the banana provides carbohydrates and the yogurt adds protein which makes it a useful option when you need something simple before exercising.
If you exercise for a long time or do intense cardio you should pay attention to your hydration before training because drinking water regularly can help you maintain performance and reduce the chance of dehydration.
If you feel tired before every gym session check your sleep schedule first because consistently sleeping too little can affect your energy concentration strength and recovery even if you are eating well before your workout.
You can eat whole wheat toast with peanut butter before your workout if you want a convenient snack that provides carbohydrates and some fat but keep the portion moderate and allow enough digestion time if you have a sensitive stomach.
If you are planning a heavy leg workout or a long training session try eating a carbohydrate rich meal a few hours beforehand because demanding exercise requires fuel and training while underfed may make the session feel more difficult.