First. You really shouldn't be using SugarCube v1 for even semi-new projects at this point as it has been end-of-life'd for quite a while now. SugarCube v2 is the current major version and is a significant improvement over v1.
If your settings passage does not have sub-passages, then you may use the passage() function to determine what the currently displayed/navigated passage happens to be. For example, you may wrap the link thus:
<<if passage() isnot "SETTINGS">>[[SETTINGS]]<</if>>
That will show the link as long as the current passage is not SETTINGS.
If your settings passage does have sub-passages, then you'll probably need to use the tags() function to determine whether the player is somewhere within your settings menu. For example, tag each passage of your menu with something—e.g. menu—and then wrap the link thus:
<<if not tags().includes("menu")>>[[SETTINGS]]<</if>>
That will show the link as long as the current passage's tags do not include menu.
SEE: SugarCube v1 documentation.
PS: Please tag your questions with the name+major version of both the compiler you're using (e.g. twine1, twine2, tweego1) and story format (e.g. harlowe2, sugarcube2), because it can, and often does, make a difference to the answers you'll receive and how quickly you receive them. I'd also suggest specifying the full version of each somewhere, either as additional tags (e.g. twine2-1-3, sugarcube2-1-8) or within the post, because that can matter too.
A blurb in the subject/title is not sufficient.