Issue with typing on Blade Pro 17 (2017)

I was given my laptop roughly a year ago when a person my dad worked with gave it to him, and since he didn't need it, gave it to me. Ever since I've had it in my possession, it is frustrating to type with. I have a PC so don't have the greatest need for it, but I would also like to have a laptop that doesn't take several seconds to type a single word. The issue: When using the keyboard on the Blade Pro to type, there are some keys that require either multiple presses or a few seconds of being held down to register and appear on my screen. For example, I might be typing a sentence, and all of the sudden the 'R' key will not register in my sentence. I'll have to then hold down that key for a few seconds to get it to register. This wouldn't be as big of a deal if it didn't happen as frequently as it does. I cannot type a single sentence without this issue occurring, which frustrates me greatly. I hope that there is a fix to this. Thanks to all who respond.