How to load a local plugin in CoreDNS 1.11.2

[Playit3110]

I made myself a ddns plugin with some special features and would like to test and run it. I tried to load it over the plugin.cfg file, but I just got a
core/plugin/zplugin.go:9:2: no required module provides package github.com/coredns/coredns/plugin/<plugin>; to add it: go get github.com/coredns/coredns/plugin/<plugin>

Maybe I didn't understand it correctly, so thank you for your help.