"Griffo" wrote:

I am renovating an old wooden floor and want to use danish oil to bring
out the colour of the wood. Is there anything I can use to protect it?

Danish oil is oil and dye with some varnish in it. Polyurethane
varnish is the standard on wood floors these days, and since it darkens
the wood a bit, you may not need Danish oil at first coat, depending on
the colors.

My red oak floor got a double coat of polyurethane after its sanding.
Nothing else was needed.