Is there a group that helps older people with heavy tasks?

Call the mormons. The missionaries in my area are actually advertising on FB that they are looking for projects.

I’d call the local senior citizen center or aging office to get some leads. Good luck 🍀

Something like this would be a local thing. Join Nextdoor.com, which is a network for neighborhoods. You just need to post an appeal and you will most likely get several responses in short time. Or, contact a local church or boyscout troop, or contact your local area’s Agency on Aging for information and resources.