Yes, you can definitely upgrade it. RAM is a crucial component of any laptop, including a gaming laptop as well.
Although a gaming laptop comes with a sufficient inbuilt RAM, in case you want to enhance more the system performance of your laptop, RAM up-gradation will be an ideal option for you.
It will also boost up your gaming experience a little bit higher. But it would help if you always remember that apart from RAM the Processor is also an essential aspect in your gaming laptop.
High-end games need faster-processing speed along with RAM speed as well. If your processor speed is slow, you have to face some lag in gaming, even though you upgrade the RAM.