Greenpeace Bulgaria is using a more general page, offering different engagement opportunities in terms of: jobs, volunteering and donations. Don't freak out if you see any mistakes, I used Google translate before taking the screenshot
Greenpeace Belgium has also 3 options: to register as volunteer or online activist and to join a local group.
Greenpeace New Zealand give the following 3 options: to start a campaign with the national open campaign platform, to learn more about the campaigning tools and to join a local group.
Greenpeace Southeast Asia offers volunteering guidelines and a link to register for anyone interested
Greenpeace Canada offers opportunities to sign up for volunteer and training opportunities, joining local groups or being a green ambassador