Apple has designed the laptop to be charged with either port. Neither will damage the computer. It will regulate its own power intake and start and stop charging as it was designed.
The best advice for getting the most from your battery:
• Plug in when using the computer near available power.
• Use on battery when ac is unavailable.
• Don’t subject the computer and battery to extreme temperatures.
• Let the OS and charging circuits manage the charging.
• Try not to allow the battery to discharge deeply before plugging in. Yes, it may happen from time to time, just don't make it a habit.
• Don't obsess over battery life and/or health.
Here is Apple's guidance on the subject.
Batteries - Maximizing Performance - Apple Support
About battery health management in Mac laptops - Apple Support