Riding horses lag, Dying when hitting water, lag mid game and losing progress

I'm having multiple issues Entering my realm it says unable to join and over five minute wait loading screen for the realm. Playing on the realm I have issues every time I ride a horse. It constantly lags and will respawn me more than 10 blocks away randomly, or when leashing my horse across water and getting on it after meeting land, it will respawn me back to my home, and my horse will be gone or it will put me back in the water with but my horse is gone or more than 20 blocks away. Ive noticed I am taking fall damage and even dying when falling into water. Lastly, the game will lag mid playing on realms and all the mobs in the game freeze, but I was able to move. Then it kicks me out of the realm, as I go back into the real I am three days in the past and have lost all of my progress from that point, including items and was sent back to a previous place. I received the 1.20.51 update saying it was going to fix these things but I'm having issues with it now more than ever.