I always try avoiding planting rails on floors. This is to future-proof things. Should floors need changing, no rail removal, tampering nor workaround needed.
If staircase & upper floors are of concrete, you can use chemical anchors(Hilti, Sika, Fischer) to plant metal angles or channels on the vertical sections(beam face or side of staircase) for your balusters to bolt on to.
Here's an example of rugged treated wood anchored on the vertical beam face, not thru the floor.
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