If you need certs for local dev, use a local CA. Tools like mkcert automate this. If you need certs if a private network, either use Let's Encrypt/ACME or run

If you need certs for local dev, use a local CA. Tools like mkcert automate this. If you need certs if a private network, either use Let's Encrypt/ACME or run your own CA and add the CA cert to your machines.