Hey estevan24,
I see that your Mac runs out of battery quick and the device gets warm while you're gaming. I can understand your concern, and I'd be more than happy to help you!
For your Mac battery, check your battery condition by following the steps from here: If your Mac battery runs out of charge quickly
If your battery condition is normal, try following the tips that are offered from the Maximizing Battery Life and Lifespan article.
Your Mac can get warm during normal use. Here's how you can manage its operating temperature: Keep your Mac notebook within acceptable operating temperatures
During heavy use of your Mac, it's normal for the fan to run faster than it normally would. A game that requires more processing power with higher resolution would be one example. If you feel like the fan is running loud during normal use, I recommend that you reset the SMC and see if it helps: How to reset the SMC of your Mac
I hope this helps!
Warm regards.