It depends on whether the object was charged before the electrons came along.

— Electrons carry negative charge.

— If the object was originally neutral, then the extra electrons brought extra negative charge with them, and the object became negatively charged.

— If the object was positively charged to begin with, then it could be
charged either way after it has gained electrons.

… If there aren’t enough electrons to completely cancel out the original
positive charge, then the object will still be positively charged (although
not as much) after it has gained the electrons.

… If there MORE electrons than it takes to completely cancel out the
original positive charge, then the object will be negatively charged after
it has gained the electrons.

… If there are EXACTLY the right number of electrons to completely
cancel out the original positive charge, then the object will be neutral
(no charge) after it has gained the electrons.