How many should we charge a gaming laptop? or Is it good to play games on the laptop while charging?
It’s not good, it’s recommended. All the laptops have an in-built mechanism that switches to AC power when the battery gets fully charged, and the only trickle charges the battery. You could remove the battery but that wouldn’t be a lot beneficial. Also, your GPU might get bottlenecked when running on battery power due to power saving. And then there is the classic problem of gaming on battery, “S#!t, that didn’t save”. And believe me, it’s frustrating when you almost complete a two-hour-long level.
TLDR; There is no problem when playing games on the laptop while charging, in fact, recommended.