You did the first step right with the PVA to seal. You need a proper floor paint which is generally grey or red from most suppliers. You can get different colours but that's more expensive. A decent hardware/builders providers will supply it. You need to put down a few coats with the first ideally thinned. Just use a roller with a handle and a tray.

If your floor is power floated and it gets any sort of traffic the paint will eventually lift.