What to do if MacBook Pro 2017 uses more wattage than the charger can give?

I wanted to ask, what to do if MacBook Pro 2017 uses more wattage than the charger can give? Why I am asking this or thinking this might be a problem? I tried to play some games on BootCamp (playing games on MacBook is another discussion, no hate please) on settings where I got 60FPS without lag but the problem is that my battery is discharging at the time I am playing. I can not recognize the problem on macOS though.

If I bought the mac couple days ago, first they gave me fake charger which f*d up my mac and wouldn't charge at all. Still can not believe that I buy new Mac and get fake charger with it. Then I went back to the store and asked for new Original charger which I then got. I can not see any more problems than the above I described.

Can anybody tell me what to check, what to do, who to contact with? Any help is much appreciated.

You should check the power of your charger and then check the power required for your MacBook Pro. I think you need a 87 Watt charger but smaller chargers will work although they may exhibit the problem you see. You can check the required charger and cables for your computer here.

If your charger is less the 87 Watts your best options are to go back to wherever you bought the computer and explain your problem or buy a new charger from Apple.