Howdy eda44,
It's great to have you in the Apple Support Community. We understand that you’d like to know which steps to take to ensure that the battery of your Mac lasts as long as possible. You also have concerns about the battery life. We are happy to guide you.
Here are some great tips that will help you maximize the lifespan of your battery.
“Tips for MacBook Air and MacBook Pro.
Update to the latest software.
Always make sure your MacBook is using the latest version of macOS. If you’re connected to the Internet, macOS automatically checks for software updates every week, but you still control when the updates are installed. To confirm that you’re using the latest software, go to the Apple menu and choose Software Update.
Optimize your settings.
Energy. The Energy Saver preference pane includes several settings that determine power levels for your MacBook. Your MacBook knows when it’s plugged in and runs accordingly. When using battery power, it dims the screen and uses other components sparingly. If you change this setting to maximize performance, your battery will drain more quickly.
Brightness. Dim the screen to the lowest comfortable level to achieve maximum battery life. For instance, when watching a video on an airplane, you may not need full brightness if the cabin lights are off.
Wi-Fi. Wi-Fi consumes power, even if you are not using it to connect to a network. You can turn it off in the Wi-Fi status menu in the menu bar or in Network preferences.
Applications and peripherals. Disconnect peripherals and quit applications not in use. Eject an SD card if you’re not currently accessing it.
Plug in and power on your MacBook to charge other devices.
Make sure your MacBook is plugged in and powered on when you’re using it to charge other devices via USB. Otherwise those devices may drain the battery in your MacBook faster than normal. If another device is connected to your MacBook when it’s turned off or in sleep or standby mode, the device’s battery may drain.”
Maximizing Battery Life and Lifespan
Although your Mac can get warm during normal use, are you using it where the ambient temperature is between 10° and 35° C? Please review this article related to acceptable operating temperatures: Keep your Mac notebook within acceptable operating temperatures
You'll also find some references in that article to the fans and steps you can take to reduce high temperatures.
Have an awesome rest of your day!