how to completely uninstall minikube from ubuntu 20.04

First, run minikube delete to remove minikube VM (or container if run with docker driver), virtual network interfaces configured on the host machine and all other traces of minikube cluster.

Only then you can safely remove its binary. The way how you should do it depends on how you've installed it, but as you can see here, there are not so many options.

If you've installed it by running:

sudo install minikube-linux-amd64 /usr/local/bin/minikube

you can simply remove the binary from /usr/local/bin/minikube directory as what the above command basically does, is copying the binary to the destination directory. If it's installed in a different directory, you can always check it by running:

which minikube

If it was installed using dpkg package manager:

sudo dpkg -i minikube_latest_amd64.deb

you can search for it with the following command:

dpkg -l | grep minikube

If it shows you something like:

ii    minikube    1.17.1    amd64    Minikube

you can completely remove it (with all its configuration files) by running:

sudo dpkg --purge minikube