In my experience, people will often volunteer at the beginning of their career before they have a family, or towards the end when their kids have left the nest. There is also a middle period when for enrichment or to take a break from regular routine, a professional including trades and technology folks take on something that is likely short and focused and aligned with their skill set.
Decades ago, I joined CUSO International as a young man for a two-year teaching stint in Nigeria, and just last year I volunteered as a semi-retiree for a short assignment in the Caribbean as a Catalyste+ Advisor. So I have seen both ends of the volunteer spectrum.

These days CUSO International offers a variety of short and longer term assignments. I posted about this organization before. They regularly announce up-coming volunteer positions in the Caribbean, South America and Africa.
Cuso International | Skills to share. Futures to build.

Catalyste+ generally provides more specialized services. Specialists are called neither volunteers nor consultants but rather Catalyste+ Advisors.
Global Hub for Economic Development | Catalyste+
One program they had in the Caribbean is winding down just as new programs are opening in the Philippines, Mongolia, and Viet Nam.
South of the border where thousands of development workers were laid off after cuts to USAID , there is current information on the DEVEX Career Hub website about the value of volunteering while waiting for a full-time development job.
As a closing note, let me say one can combine volunteering with other work. I still do some consulting.
GOOD LUCK, whatever you decide.
