Tips for a friend visiting Iceland
If you travel on a budget, bring some snacks, eg. nuts, seeds, protein bars. Iceland is generally quite expensive and so are groceries. If you have some free space in your backpack, take stuff you can nibble on on the road.
Transportation tips for France
Lease a car. It would be impossible to reach the most beautiful of the tiny villages without one. And not to be intimidated at the markets, they can be intense but worth it for the delicious produce you'll come home with.
Packing tips for Portugal
If you're going in the spring or autumn, bring layers! Summer clothing is likely suitable during the day, but it can get chilly in the evening. A light jacket or sweater should do the trick, but I'd recommend bringing a rain jacket too - just in case.