Many of the menus in Spain are a fixed price with some choices for each of the meal courses. This is a convenient buying option to be able to pick a price and then the items available within that price.
You should notice these two words on the menu.
incluido: Usually somewhere at the bottom these item indicates what additional costs might be included (or not, as in incluido) the bill, typically the VAT (tax) or IVA (in Spanish). But you may also encounter that one of the items as suplemento, an extra charge for this particular item.
Or, for the cognate incluir is the verb and (incluyo, incluyes, incluye, incluimos, incluís, incluyen are conjugations that might be used), notice that no is not which may proceed these various forms to indicate something is not included.
To avoid surprises you should scan the menu carefully and make sure you understand the possibility (or exclusion) of additional fees added to the check.
Note that tipping is typically not done, although: a) in restaurants primarily for tourists tipping may be standard (or at least they’ll try to convince you it’s appropriate, given you are used to it in other countries), or, b) a small “round up” in the bill may be just a bit extra to supplement the compensation your server will receive.