To Get Google Tag Manager Code ( GTM Code ) at Any Time
Navigate to Google Tag Manager
If you already Created containers, this page navigates to display all the containers list
Select Container ( click on the container for which you like to get the code )
or
The same thing can select like this
click on "All Account" from the top bar and
select the correct "Tag Manager Account" and then "Container"
And then Click on "Admin"
At the "Container" section Click on "Install Google Tag Manager"
Now we got the Google Tag Manager code
Next
The "script" part have to add inside the head tag, and "noscript" tag have to add in after opening body tag