Unable to build Kubernetes in Ubuntu server

Trying to build and debug Kubernetes from source code - from this documentation

But when running

sudo ./hack/local-up-cluster.sh

I get error saying:

To ignore the vendor directory, use -mod=readonly or -mod=mod.
To sync the vendor directory, run:
        go mod vendor

If I do go mod vendor I get very many “No such file or directory”:

make: Entering directory '/home/ubuntu/go/src/k8s.io/kubernetes'
make[1]: Entering directory '/home/ubuntu/go/src/k8s.io/kubernetes'
find: ‘vendor/k8s.io/apiextensions-apiserver/examples/client-go/hack’: No such file or directory
find: ‘vendor/k8s.io/apiextensions-apiserver/examples/client-go/pkg/apis/cr’: No such file or directory
find: ‘vendor/k8s.io/apiextensions-apiserver/examples/client-go/pkg/apis/cr/v1’: No such file or directory
find: ‘vendor/k8s.io/apiextensions-apiserver/examples/client-go/pkg/client/clientset/versioned’: No such file or directory
find: ‘vendor/k8s.io/apiextensions-apiserver/examples/client-go/pkg/client/clientset/versioned/fake’: No such file or directory

How do you build/debug and run Kubernegtes from source code?