Catalonia (Catalunya in
Catalan) is one of the seventeen Autonomies in which Spain is divided. They are more or less equivalent to States in the US.
Catalunya's official languages are
Spanish and Catalan; its capital is
Barcelona.
There's no province of
Loredo. You have already found it: it can only be Lerida (Lleida in
Catalan). However, it will be impossible for you to find anything about Isidro Obiols knowing only he was born in the province of Lleida: you need to know the specific town where he was born.
And there's also the fact that in the 1820's there was no Civil Registration (created in the 1870s), only baptisms, and many parish books were burnt during the
Spanish Civil War (1936-1939).
Ramon Monclús