Can't add ppa:certbot in Lightsail

Hi, I'm following this tutorial to add a Let's encrypt cert to my Lightsail instance, but when I try the step

sudo apt-add-repository ppa:certbot/certbot -y

I get this error message:

Exception in thread Thread-1: Traceback (most recent call last): File "/usr/lib/python3.9/threading.py", line 954, in _bootstrap_inner self.run() File "/usr/lib/python3.9/threading.py", line 892, in run self._target(*self._args, **self._kwargs) File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 688, in addkey_func func(**kwargs) File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 386, in add_key return apsk.add_ppa_signing_key() File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 251, in add_ppa_signing_key if not self._recv_key( File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 176, in _recv_key res = subprocess.call(self.GPG_DEFAULT_OPTIONS + [ File "/usr/lib/python3.9/subprocess.py", line 349, in call with Popen(*popenargs, **kwargs) as p: File "/usr/lib/python3.9/subprocess.py", line 951, in init self._execute_child(args, executable, preexec_fn, close_fds, File "/usr/lib/python3.9/subprocess.py", line 1823, in _execute_child raise child_exception_type(errno_num, err_msg, err_filename) FileNotFoundError: [Errno 2] No such file or directory: 'gpg'

I appreciate any help on this!

Best, Dow