Troubleshooting
Forms or Analytics say "Deploy first"
Some tools only work once your site is live.
Why it happens
Forms collects messages from real visitors, and Analytics counts real visits. Neither has anything to show until your site is on the internet, so both ask you to publish first.
How to fix it
Publish your site. See Publish your site. Publishing needs a paid plan. After that, open Forms or Analytics again.
Analytics only counts visits that happen after your site is live, so it starts empty. Visit your own site once to check that visits are coming through.