My toilet tank can pump water, but it can't flush. What happened? How can I fix it myself? !

I don't know what you mean. "The toilet tank can pump water" means that the tank can hold water? "Can't flush" means that the water doesn't enter the toilet, or you can't flush the stool? If the water doesn't flow into the toilet, the drain valve will be broken. Just change it. If you can't flush the stool, it's blocked. Buckle the hole in the water with a leather bowl that pokes the toilet and press it hard to clear it. If not, please ask the property management for help.