My friend fully thinks he can beat Amanda Nunes

My friend thinks he can beat amanda nunes in a fight. He is 6'5", 280 pounds never trained in mma and thinks that he can fully take out amanda nunes tomorrow. His strategy is to overpower with his strength and get her on the ground he wants to use his weight to keep her pinned. He is adamant that given her skillset it would be difficult for her to get out of that position given his size and weight.

Could you guys please let him know the truth, he will be reading this reddit and fully believes this with all his heart; maybe he will come to his senses and realize once he sees everyone's opinion. He also wants to know at what point does size not matter in an mma fight. Thanks.