It sounds like you may have changed some settings in Start11 as the defaults would be as you want.
On the taskbar page in Start11 settings find the taskbar right click menu section and expand it.
There are two options. The first one sounds like it is disabled on your computer. Turn this on.
By default Windows 11 will only offer you taskbar settings when you right click on a blank area, again the next option in Start11 settings lets you return this to a more normal menu. So enable this.