Random effects and reverting

The bug is a very bad one and kept causing me and my friends to die in strange ways. One of them were in a nether fortress but me and anotherbone were mining for anvient debree when he got an extreme wither effect that would do 3 hearts of damage in less than a second similar to the instakill dragon breathe. Later on I was looking for his things but I got the effect and it left me at half a heart. It was very bad and it appeared it would shift because I got it in another area while getting out of the area. It wasbnot only happening in the nether but also in the overeorld. Things were getting quite out of hand so we decided to revert to a backup of the realm from 35 minutes ago. We thought it was fine but then we got hunger that would instantly get us to 0 hunger bars. Some of us even got slowfalling when we didn't even have any slow falling potions. But one of my friends even drowned while he wasn't sufficating or underwater, not only that but we were getting enchanted golden apple absorption hearts when the only one thats out in thebopen is in our cave area while we were in the nether. But later on my friend told me that things that had names or enchantments like protection would have no names and no enchantments. I don't know what's happening but it could be confusing players and chunks or a problem in the world.