I do believe a lot do, probably not always accessible on large scale or very narrow selections for large scales.
YALI, UN bodies, NGOs offer volunteering platforms.
One might consider starting with the local associations, gatherings, growing structures and so on.
This session is a result of some years of secret space volunteerism, training (all inclusive with or without certificates...)
A volunteer is recognised by their ability to serve and willingness to give in for a course.