Hi Alexis!
If you don't see the seekbar at the bottom, it means it was turned off in the player. Go to Home tab in Storyline, then Player. It should take you straight to the Features section of your player settings. In the Features section, at the bottom, you'll see Player Controls and you want Seekbar to be checked.
As for the "untitled scene" with the untitled slide, go into the Menu settings of the Player, and delete the scene there.
You have a lot of flexibility with how you want your player to look and all of those options are outlined here!: https://community.articulate.com/articles/articulate-storyline-360-user-guide-how-to-work-with-the-player