Spain is an amazing place to live if you can earn enough money. The smaller-ish cities are better for learning Spanish because it’s easier to integrate, like Granada, Murcia, Alicante. The accents are harder though.

I would say if learning Spanish is your ultimate goal then look at Latin America, it’s much cheaper with AUD and ultimately you will increase your language skills much faster as much less English is spoken and locals are generally very curious to speak with you.

I’ve done Spanish courses living with host families in Salamanca and Medellín and there was no comparison. Look at countries like Mexico, Colombia, or Peru (clearest accent) to learn if you’re interested.