If you have a design that requires impedance control there are numerous tools and CAD systems that will allow you to calculate the required track width, track clearance and board stack properties to achieve your impedance values.
However, how can you be sure that what you have calculated is suitable for PCB manufacture?
It makes far more sense to work closely with your PCB manufacturer from the offset (they want you to) and let them configure a layer stack that will not only meet your requirement but will be manufacturable, anywhere.
The CAD tools can then be used to verify their calculations and the utilisation of their constraints management would ensure that your design meets the required rules.
This method ensures what you design is manufacturable and you don’t incur costly rework and project delays.