Then they shouldn’t interrogate you. The point of Miranda is to confirm that you know of your right to not participate in the investigation, but it’s told to you in the context of asking you to give up those rights. If it’s not clear that you aren’t understanding this, then the police run the risk of having whatever you say get suppressed because you didn’t make a knowing and intelligent waiver of your rights.
(From a practical standpoint, police will usually have you sign a piece of paper that memorializes the fact that you were advised of your rights, understand them, were not made any promises to give them up, and are voluntarily choosing to waive them in order to speak with the police)
And, if in response to the question “do you understand these rights?” you ignore the question and just start telling what happened, you’ll likely be deemed to have made a voluntary statement, and it will he hard to argue that it was a coercive interview unless there’s some extraneous facts to show that you really were confused about what was going on.