'93 Escort Cylinder Head problem

Hi all,
my wifes '93 escort blew the hose of the bottom radiator connection. I put it back on, when I looked at the radiator cap, it looks like it's got a layer of oil on the cap, plus there's oil residue inside the radiator.

When we start the car, even when warm it blows water out of the exhaust.

Is the cylinder head likely to be cracked, or just a bad head gasket?

How long does it take to change a head gasket?

Thanks for any help

Regard Dave