If you ask someone a question or to do something where you are telling them the answer or the way to do it in the question im sure there is a phrase or word to describe it.... what is it?
There is the expression "Hobson's choice" which describes a literal one-choice situation, for example, "take it, or leave it". Early car manufacturer Henry Ford famously said that customers could have "any colour so long as it is black", which is a humorous play on this idea - their choice is to either buy a black car or not buy a car at all.
If you mean to imply that someone is offering "two choices" but there is some kind of deception involved that means really, any choice is an illusion, there are a few different expressions.
"Equivocation" is the use of ambiguous language to conceal the truth or to avoid committing oneself, or calling two things by the same name. Stage magicians use this term to describe tricks where a participant is seemingly given a choice but they both lead to the same result.
There is also a psychology term "the illusion of choice", but to be honest this refers to a far deeper concept that questions whether anything we do is of our free will.