You mean, "Remove"; or, "Detach" an individual/person from your "Ancestral" lines; as, we do not a "Tree" in "Family Tree" of 'FamilySearch'.
That is easy ..
BEFORE you do ...
Unless you added/included them in your "Ancestral" lines, by mistake/in error ...
IF, they were added by another User/Patron; THEN, do your Research (ie. 'Due Diligence'); and, Make CERTAIN that, in fact, that their position in your "Ancestral" lines is NOT correct.
IF, you have done that; THEN ...
Here are some "Knowledge Articles" in 'FamilySearch;
How do I correct parent-child relationships in Family Tree?
A person in Family Tree has the wrong spouse
I hope this helps.
Related 'Question', in 'Group' being "Getting Started on FamilySearch" ...
how do I delete someone from my family tree?
Just in case you were not aware ...
Most new (and, some old) Users/Patrons DO NOT understand the basic nature and premise of "Family Tree" of 'FamilySearch', when they join in.
Please let me explain ...
We do not have our OWN "Tree" in "Family Tree" of 'FamilySearch'.
We ONLY have "Branches" (ie. Ancestral" lines), that are interconnected, in this SINGLE "One" World "Tree", for all of us, that is "Family Tree" of 'FamilySearch'.
"Family Tree" of 'FamilySearch' is NOT like 'On-Line' "Websites" (eg. "Ancestry_com"; or "MyHeritage_com"; or, the like); and/or, 'standalone' personal (computer) programmes (eg, the OLD, now no longer supported, "PAF"; or, "Ancestral Quest"; or, the like).
We DO NOT have "Private"/"Personal" 'Trees' in "Family Tree" of 'FamilySearch' like other 'On-Line' "Websites"; and/or, 'standalone' personal (computer) programmes.
We do not even, own; or, manage; and, are NOT even responsible for, the "Deceased" individuals/persons in "Family Tree" of 'FamilySearch'.
"Family Tree" of 'FamilySearch' is built on a "Open Edit" Platform - hence, why any registered User/Patron can "Edit" (ie. Add, Delete; and/or, Change) ANY "Deceased" individual/person in "Family Tree" of 'FamilySearch'.