Here is the full list of all 18 Sheltered achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Trap 100 animals on the shelter surface (cumulatively)
Subdue an enemy in combat
Win combat using a gun
Survive 100 days
Fully upgrade all systems
Fully upgrade a system
Take the RV out on an expedition
Have 5 or more plant stations in the shelter
Grow and harvest a plant from the plant station
Collect all 10 tools (on a single game)
Search 200 locations (cumulatively)
Travel 1000 miles (cumulatively) on the map
Travel 500 miles (cumulatively) on the map
Trap an animal on the shelter surface
Travel 100 miles (cumulatively) on the map
Survive a week
Craft your first object/item
Upgrade a system once