I need a link to buy Polyurethane oil to seal my tortoise table

[RyanDSC]

I am a bit confused with what polyurethane oil to use as it always comes up with varnish. I want to seal my tortoise table with water based Polyurethane oil. Can someone please forward me a link to buy some. Thank you. Hope i am making sense with what i'm asking as this has confused me when researching. Thank you very much 😊