In Google Chrome and Atom (and probably also in other programs), it's possible to 'Go to tab # 1' by pressing CMD + 1 (for Mac) or SUPER + 1 (for Windows). I love that feature more than I love my mother, - but I can't find anyone else requesting a way to set it up in PhpStorm (for some reason).
I know that I can navigate to other tabs using the Switcher or pressing CMD + [ or CMD + SHIFT + [. I have read all of this page: https://www.jetbrains.com/help/phpstorm/2017.1/navigating-between-editor-tabs.html - without any luck.
I've also gone through the Keymap in the settings, looking for a way to set it up - but I can't find a way. In the Keymap - there is no actions called: 'Go to tab # 1' nor 'Go to tab # $var'.
There is no such built-in functionality available.
https://youtrack.jetbrains.com/issue/IDEA-68324 -- follow this ticket (star/vote/comment) to get notified on any progress.
But you may use GoToTabs plugin for such browser-like tab navigation.