@IrishMel2018 , sounds great
I'm a bloke, so can't respond to all of your questions.
On the other hand I have walked alone from south central France to north west Spain, in south east England and, with my adult son, on a more limited stroll in Scotland.
I like walking alone best. I'm in control of what I do, or don't do, each day. And of who I chat to at stops during the day. And where and when and what I eat. But it's only for a season (week, month, whatever). Then normal transmission resumes at home.
Your preparation, your stamina etc will guide you as to the distances you will do each day. Some people on trip like this like every day buttoned down. Others take each hour, each day, each encounter as they come. You will be able to find out which you are for yourself.
Five or six days walking would get you to, or approaching, Estella / Lizarra. There is a hop on bus service between Pamplona, Estella and Logrono.
The timetable is here.
Being a bit of a rebel I often chose to walk on nearby roads, on the usually generous shoulder on the left, facing the on coming traffic. Most of my training is on roads, so I was comfortable with that.
So, kia kaha (take care, be strong, get going)