Hi Ebrovoice, This is what the leaflet from the mosses tells us:

-Everyone has the right to healthcare and merely needs to be
registered in Catalonia.

-Newcomers who do not have their administrative papers in order
and are not on the register have the right to emergency
healthcare in health centres or at home, for both accidents and
serious illnesses.

-To obtain a health card you should go to your nearest health
centre with your record of registration and complete the application.

There also is a lot of info (also in english) on www.gencat.cat and there is a helpline (the info is in english, so i assume they also have english operators....)

24-hour Sanitat Respon helpline: Call 902 111 444, the Sanitat Respon helpline number, for any question your have about your health or about health-related issues.

Hope this helps,
Mark