I don't understand what your issue. What is missing? And from where?

i'm trying to add my phone to Firefox account. the instruction i've gotten are to click on the firefox button at the top of the firefox window. next click on set up sync. when i click on firefox on the top left of the screen i don't get a set up sync option to click on. just a sync now option.

Have you tried clicking on the Sync now option to see what happens?

If you have Sync Now then sync has been setup on that computer.

You can inspect the sync settings in Options > Sync

• https://support.mozilla.org/kb/how-do-i-set-up-firefox-sync
• https://support.mozilla.org/kb/add-a-device-to-firefox-sync
• https://support.mozilla.org/kb/how-do-i-manage-my-firefox-sync-account

• https://support.mozilla.org/kb/firefox-sync-troubleshooting-and-tips

thanks for your help...