I highly recommend HelpX to get a really good feel of the lifestyle in foreign countries. Rather than just staying at someone's place like Airbnb, you do light work for your host in exchange for free room and board. You get a place to live in a place where locals actually live, homecooked meals in the local style, when your host don't feel like cooking you get taken out to eat at places where locals actually eat, get shown around the local sights by your host on evenings and weekends, and you also get to experience some of the work they do. It's an incredibly easy, low-cost, and effective way to temporarily live somewhere.
I stayed with 2 families in France that way, and got to label wine bottles at a local domaine (vineyard), drink their wine at dinner, shovel horse manure at a farm, harvest honey, ran to the boulangerie for bread, went shopping at the local supermarket, got shown around a spectacular nearby castle and a monastery carved into a cliff that I'd never heard of, ate cheese and charcuterie at their favourite restaurants, they made an effort to cook traditional food like raclette and canneles for me to try.... really I can't rave about the experience enough.
This sounds tempting, but I have a hard enough time arranging regular visas on international trips, and work visas (even short term ones) sound like a nightmare and a half...
Sorry, late response, but most countries (including France) require a work visa for things like unpaid internships, or being compensated in any way. Paying for board/food counts as compensation.
Look at it from the perspective of the US -- you can't just recruit programmers from India, have them come over "on vacation", pay them in room/board, and expect to not have any problems with border control. Work is work.
I don't know the official answer, but given that it's all under the table, short term and no money is being exchanged, I think you'd be crazy to even try getting a work visa. I'll be honest that it didn't even cross my mind.
I stayed with 2 families in France that way, and got to label wine bottles at a local domaine (vineyard), drink their wine at dinner, shovel horse manure at a farm, harvest honey, ran to the boulangerie for bread, went shopping at the local supermarket, got shown around a spectacular nearby castle and a monastery carved into a cliff that I'd never heard of, ate cheese and charcuterie at their favourite restaurants, they made an effort to cook traditional food like raclette and canneles for me to try.... really I can't rave about the experience enough.
https://www.helpx.net/