Oh! You can either do it on a PC or (in my case) if you have an android phone (samsung for me), you can click on the three dots at the very right top corner next to the mangago.zone link, then scroll down and before the settings option there should be one that says "desktop site" click on that, it'll made the website a bit different. Then simply click on any picture in a manga and it'll bring up a small menu that says smth like, "add to album"
Hope this is easier to understand":)
https://www.mangago.zone/home/photo/13253269/#image
Sorry its this https://www.mangago.zone/home/photo/31972950/
I see that in mangas there is a section with pictures that sometimes are commented. How do I do that???