Here are a few websites for working and volunteering abroad:
Workaway is a platform and service to connect world travelers and locals with families and projects around the world (Hosts) to enable cultural exchange, learning possibilities, skills and information exchange and to help out in countries across the world. Many times you get accommodation and sometimes food in exchange for your work.
WWOOFing is learning and sharing sustainable living practices through volunteering on organic farms.
You usually get accommodation, food and sometimes learning opportunities in return for your volunteer work.
HelpX is an online listing of host organic farms, non-organic farms, farmstays, homestays, ranches, lodges, Bed &Breakfasts, backpackers hostels and even sailing boats who invite volunteer helpers to stay with them short-term in exchange for food and accommodation.