Can you make fake conversations?

Look I may be stupid but need to know can you make fake whatsapp conversations. I just tot screenshots of my man messaging another girl apparently for one whole year together behind my back. She never knew about us being together. I just need to know. He claims it's all fake and I WANT it to be fake 😭 we got kids and it's just HARD I want to work through it but if he can't be honest and fess up it's hard. Especially if its real. I rather he be a man and fess up and not continue lying. I wasn't sent a years worth of messages just most recent ones like last night ones. She had no photos of them together. Which if she did would just make him realize he needs to fess up. I've been feeling like I'm worthless and just want to pretend it's all fake. I did talk to her she's the one who sent me a few screenshots. She never knew about us still being together I was just his baby momma apparently. I keep praying it's fake. She said she got pregnant 3x lost 2 and aborted 1. And bought him 3 vehicles supposedly.