The idea of “defunding the police“ is to re-allocate funds towards services that are better aligned with the problems at hand in a given community.
Take drug addiction as an example — Instead of funding more jails and more officers, “defunding” would allocate that money towards addiction specialists, rehabilitation facilities and programs to help people recover, get jobs, and rebuild their lives.
In other words: A shift towards funding preventative care more, and reactive use of force less.
It doesn't mean the police go away entirely.