Need help with getting old photos back

In May 2017, i switched from an iPhone 5s to a iPhone 7. I didn't know how to get the photos back, but my mother told me that it was all in the SIM card. I switched my iPhone 7 SIM card with the iPhone 5 SIM card. Nothing happened. I just ignored it and decided to start new. I thought i would find out how to get it soon. About 6 months later, I found out my mom gave my phone to one of her friends, and my phone got stolen. I don't know if my apple account was still on my phone or not. About 2 months ago, I got a new iPhone 8. I was trying to get my photos from my iPhone 5 but nothing worked. Is there anyway i can get both my iPhone 5 photos and my iPhone 8 photos?