What does Linda mean?
In Spanish and Portuguese linda means 'pretty, beautiful' (from Latin/Romance). NOTE: the name also has an independent Germanic source, the element lind 'soft, tender' (as in names like Rosalind); so 'pretty' is the Romance reading, 'soft/tender' the Germanic one.
What does Mía mean?
Primarily a short, affectionate form of María (ultimately from the Hebrew Miriam, meaning uncertain). Its popularity in the Hispanic world is reinforced by coincidence with the Spanish possessive mía 'mine' (also the Italian word 'mine'), though that resemblance is not the name's actual origin.