The phrase "overwhelming task" means a task or job that feels very difficult or too much to handle. It may make you feel stressed or worried because it seems like there is too much to do. Full definition
Don't let the seemingly overwhelming task of sorting through 401k options stop you from participating in such a plan. (gobankingrates.com)
There are many overwhelming tasks for a parent when it comes to planning the arrival of a newborn. (earlymomentsmatter.org)
Once you've decided where to register, the seemingly overwhelming task of figuring out all the things you'll need for the new baby soon follows. (care.com)