This merch shelf feature is still expanding / rolling out to all eligible creators and is currently available to certain eligible creators. You can find more details here: https://goo.gl/4zu2jj . Hope this helps!
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
This merch shelf feature is still expanding / rolling out to all eligible creators and is currently available to certain eligible creators. You can find more details here: https://goo.gl/4zu2jj . Hope this helps!