Am having problems retrieving my current node ID a custom module

I have a new route and the yml file looks like this: rsvplist.form: path: ‘/rsvplist’ defaults: _form: ‘\Drupal\rsvplist\Form\RSVPForm’ _title: ‘RSVP to this Event’ requirements: _permission: ‘access content’ From the module root directory, I have src/Form/RSVPForm.php, and inside is where I have the build form function that looks like the following: public function buildForm(array $form, FormStateInterface…