Belgium, Spain and Portugal are sure thing for me but I don't believe in Italy and England.
Let me start off by saying that i am not a fan of matches being scattered across Europe with 11 cities/countries serving as hosts. Teams like Italy will play all of their group-stage matches at home, whereas their opponents will have to travel from Azerbaijan to Rome, what the heck is that, how is that not an advantage, right? I know Turkey is leading their World Cup qualifiers group, they had an impressive win over the Dutch, they have decent players (some of whom play in Serie A), but i can't see them doing much more than scoring a goal in the opener. I see the Azzurri going 3/3 in their group without much hassle. My point, add Italy to the sure thing list, at least i will.
I believe most of the nations are in camps right now, they are not moving around all that much they are moving just like everyone else. When you are in a camp you just move from one nation to where the cup will be on last days and then you spend the day there easily without a problem, remember these are professional players and the problem is the fans in the stands and not the travel.
I would not put anyone in the sure fire thing, there is no way that any team in this cup could be "sure fire" because every team is good, which means Italy is definitely not a sure fire thing there is no way they could be, but I would not say Belgium or Spain or Portugal could be sure fire neither.