the two sided foliage material might be a good option - it's a little simpler to operate than the subsurface scattering material and supports cast shadows (eg from the tent poles / stuff inside)
You'll want to investigate subsurface scattering for the tent material, then put a lightsource inside it. Might need to play with camera settings to replicate that photo as well. https://docs.unrealengine.com/4.27/en-US/RenderingAndGraphics/Materials/HowTo/Subsurface_Scattering/…
Is it disappearing, or is it hard to see? If the former, you've broken something in your material. Subsurface influences the color of your material, because its faking the light bleeding through. You want to have a mask to influence how much SSS you have and where. Play with settings, read the documentation fully,…