Find the kitchen to prepare meats and potatoes; eating raw food can lead to health issues.
Don't always stay on the MG42 when enemies are close; the AI can be very accurate. Sometimes it's better to wait in a room and pick them off as they enter. WW2: Bunker Simulator on Steam WW2: Bunker Simulator Free Download (v13.10.2022)
You can download a free trial version on Steam to test the mechanics before buying. Find the kitchen to prepare meats and potatoes;
Search enemy bodies for chocolate, ammo, and medicine (bandages/pills). Bunker Defense: WW2: Bunker Simulator Free Download (v13.10.2022)
Use MG42 stations for infantry and anti-aircraft guns for planes.