@WalkerForever, I agree with
@C clearly that you must have better access to information about the ins and outs of restrictions on entry into Spain and restrictions on mobility within Spain than all of us together as you live in Spain's neighbour country Portugal, read news in Spanish and are obviously a resident or even a national of Portugal. In addition, here you are likely to receive information about conditions that apply to other forum members but not to you.
As to what you presumably want to know: I happened to have come across a recent article in El Pais that explains
why Spain is closed to domestic tourism but open to Europeans and while regional borders remain largely sealed, 274,242 foreign travelers arrived in January thanks to different rules adopted by central and regional authorities.
I think the article also addresses differences between travel across Spain's air borders, sea borders and land borders. In short, Navarra won't and can't stop you from walking
from France
into Navarra. And Spain could but doesn't and hasn't done so for quite a while. However, like most of the discussions around this topic during the past months and weeks, the discussion is mainly of theoretical interest, without much practical value for readers of this forum.
Article here in
English (translated by El Pais) and in
Spanish.