Research on volunteering describes associations with health, not a guaranteed increase in lifespan.
A lower mortality risk during a study is not the same as living 22% longer. Observational studies cannot establish that volunteering caused the difference: health, income and social connections may also matter. These results do not establish a medical benefit from buying gifts or using a wishlist.
Choose ways of helping that fit your energy, time and budget. Giving is not a substitute for healthcare, and you do not need to spend money to support someone.