If you want to install laminate flooring on your stairs i would recommend that you do a lot of research and find the information you will need to do it correctly.
How to install laminate flooring on stairs video.
Once this is done measure and cut out your pieces of laminate to make tread pieces riser pieces and stair nosing.
Stair tread and nosing installation.
Stair tread gauge http amzn to 2i3slng subscrib.
You can also use them to finish your staircase and create a perfectly harmonious interior.
Alternatively you could cover the overhang with plywood to make it level.
Installing laminate flooring on stairs can be tedious and time consuming and is a lot different than installing laminate flooring on a floor.
However installing laminate flooring on your stairs is a completely different matter.
To install laminate flooring on stairs start by removing the overhang or the underside of the stairs with a jigsaw.
Avoid ugly gaps nail holes.
Watch installing laminate on stairs.
You need to take care of the treads risers and stair noses which can get a bit complicated at times.
Learn to do tricky things like stair noses.
Things i mention in this vid.
Watch laminate floors installed on stairs professionally properly fast.
You have to ensure that there are no gaps and spaces in the flooring and it is complete and perfect in every way.
Quick step planks not only look great on the floor.