help! please!

Good afternoon. I kindly ask you to do something, fix bugs or give instructions on how to fix errors. There hasn't been such an update for a long time. What we have noticed during this time:
-Make Code works worse than 5-6 years ago, with bugs, programming code does not load well
-Not on all computers the program update worked
-Some computers with the same updated versions do not connect to each other
-On some computers, the code with pictures does not scroll, enter the IP
-The world itself with huge bugs, heavy, works with a huge delay: textures do not load, mobs stand motionless, if a block is broken, particles do not fly out, chunks do not load at the edge of the world, enchantment does not work
-Interesting, but on several computers inventory "E" does not turn on, if you reset the keyboard settings, nothing helps, on some machines, after the update, the buttons for moving and breaking blocks are changed.it is very hard to work, children refuse classes, do not want to work in this version.
Help me please. What to do, what settings to set ...