Modern PSUs come with a built-in electrical chips (I've forgotten what they're called). So in case of a voltage fluctuation; they automatically lower or raise the amperage to avoid hardware damage.
I wouldn't recommend buying a gaming laptop here. First; they're EXTREMELY overpriced to being with and even if you're willing to pay a hefty amount; remember that they constantly run at 90+ degrees which means they've a REALLY short lifespan.
Their performance start to degrade after 3-4 years.
It's best to go with either a gaming PC or a console. Gaming PCs are ideal because installing pirated games on them is a piece of cake but if you're willing to pay for legit games then definitely go with a PS4 or Xbox One which can be found for around 40k-60k (Depending on configuration).
And since PS5 is on the horizon and will likely be launched this year; PS4 prices will likely drop soon as a result so it's best to wait; in case you decide to go down that road.