Typically, the taskbar is at the bottom of the desktop, but you can also move it to either side or the top of the desktop. When the taskbar is unlocked, you can change its location. See Lock and unlock the taskbar to find out if yours is locked. When you’ve confirmed that your taskbar is unlocked, press and hold or right-click any empty space on the taskbar. Select Taskbar settings > Taskbar location on screen, and then select Left, Top, Right, or Bottom.
Windows 11 does not natively offer a solution to moving your start menu, you can opt to use a registry hack detailed here. However this is not recommended and could cause issues.