Sounds like maybe you inadvertently "dragged" your bottom Taskbar to the top of the screen. Assuming you are using the Microsoft Windows operating system, try the following:
Move the Taskbar back to the bottom
1.Right click on an unused area of the taskbar.
2.Make sure that “Lock the taskbar” is UNchecked.
3.Left click and hold in that unused area of the taskbar.
4.Drag the taskbar to the side of the screen you want it.
5.Release the mouse.
6.Right click in an unused area of the taskbar, and make sure that “Lock the taskbar” is CHECKED.
https://askleo.com/how-do-i-move-the-taskbar-back-to-the-bottom/
As for your having to log in to sites, sounds like somehow your browser cookies and history got deleted.
What browser are you using?