In one of the verses of the Qur’an, it is mentioned “ask through waseelah”. Is this correct? If so, what does it mean?

I do not know about the verse in the Qur’an which says ask through waseelah. We make du’a for Prophet Muhammad (ﷺ). The waseelah term in the du’a after adhaan is the du’a that Rasulullah (ﷺ) asked us to make but he explained in another hadeeth that the Waseelah is the highest place in Paradise which will be given to only one human being and he (ﷺ) hoped that it will be him, so, we ask Allah to give that position to him. It has nothing to do with intercession in this life as those who have misinterpreted it.