Hi
You are not always installing plywood itÂs recommended, if you install it you can go ether with solid wood floor that can be install only on plywood or engineered wood floor that can be install on both ;
For the height difference between the wood floor and the tile you mill you molding
Like reducer.

Any wood flooring over concrete in contact with the earth usually requires the services of an experienced professional to get it right the first time.

Whether or not you're going to install plywood first (an obsolete method in my professional opinion), the concrete needs to be FLAT and you need to make it flat before starting the job. Wood manufacturers will state how flat that needs to be.

And, you need to know how much moisture is coming through a slab before you do anything to it or apply any flooring to it.

My concrete is not flat. With "plywood first" being "obsolete", how do we get it flat? We are doing a laminate floor.

Thanks.