If you leave your laptop powered on & sleeping, then leave the macOS default battery settings configured for "Optimized Charging" which will automatically exercise the battery for you to maintain its health. You will need to first log in (it is ok if the screen locks, just don't power it on & leave it at the initial login screen or it will just power off & Optimized Charging won't be available). See the following Apple article for details:
If battery charging is paused or on hold on your Mac - Apple Support
If you leave the laptop powered off during that time, then follow the instructions in the following Apple article for storing the laptop & its battery (you want to keep the battery charge level between 20% & 80% while the laptop is being stored.....reviewing this current article Apple has changed the upper charge to 50%):
Storing Apple Laptop to Maintain Battery Health - Apple