I walked Porto to Santiago this past October. First, the easy answer - you can purchase a Pilgrim Passport at the Cathedral. I did not spend a lot of time at the Cathedral and unfortunately did not visit the second floor where there is a 16th Century statute of St James - this is mentioned in the
Brierley guide.
Spending a little extra time in Porto is worthwhile. I walked from the Cathedral and along the river to get a sense of the area. Evenings on the river enjoying fresh seafood, listening to music and sipping wine makes it extra nice.
I stayed at Hotel Peninsular near the Cathedral - nothing fancy, but very comfortable with easy access to the Metro or to walk to the river. I used my extra time in Porto to learn to navigate the Metro and went exploring in Matosinhos. Since I walked the Cathedral and along the river, I decided to avoid some of the urban walking and began my Camino from Matosinhos so that I could walk the coastline to Vila do Conde. I believe this was one of my best choices for my pilgrimage. Unlike
Camino Frances, spending a day walking next to the ocean was very pleasant. I did not see very many pilgrims, but the walk along the water made is worth it.
From Vilo do Conde, I walked inland to Rates - this is the oldest albergue on the Portuguese route and it has the famous two-color stamp for your passport. I met several pilgrims that I would continue to see the rest of my journey.
Whenever anyone asks about time and scheduling, there are an infinite amount of answers. Everyone walks their own Camino. I believe the Pilgrims with the most freedom are those without an end date. Since I was walking Camino Portugues solo and had many extra days allotted, I would generally walk 10k to 20k per day - a few times more and some days less. The only reservation I made was to stay at Casa Fernanda. And, I stayed the night inside the fortress in Valenca and near the Cathedral in Tui. Also, I paused for the night in Teo to allow for a fresh walk into Santiago.
For me, leaving on 1 October and arriving on 14 October was a nice, relaxed pace. I'm sure many other pilgrims are a bit quicker - it's not a race.
I have yet to walk to Muxia and I've talked to pilgrims that do it in 3 or 4 days. Looking at the guidebook and the elevation, I'll probably take 5 days. Muxia and Finisterre are both worth the trip.
Have a Good Journey!
Bom Caminho!