Sealant help

So in my infinite wisdom I decided to downcycle a partially upcycled bureau that my parents bought me a decade ago. Stripped, sanded, varnished. Very happy with it. Wanted the inside a deep green colour, found Vintro all purpose paint, loved the colour, seemed it would hopefully cover some of the marks I couldn't get off....finished....and then it bubbled and peeled off...looking for advice on sealant. I am painting over old paint that I have sanded as I physically couldn't get whatever paint the 'upcycler' used inside this things without damaging the surface. It will be used as a hallway table/post storage so it needs be decently durable.

Please help?