To Implement various effects in a material such as emissive, roughness, and metallic properties in Unreal Engine

Right-click in the content browser and choose material

Rename the material and double-click to open it

Right-click in the working space and search for constants

In constant choose constant vector 4

After this double click on the constant vector 4 and edit the color using the color picker

After adjusting the color click okay and save it

They join the output of the constant vector 4 to the base color

Create a single constant using step 3 and adjust its value of it using detail pannel by adjusting the value

And you can apply this constant value to metallic, roughness, emissive color etc...

For emissive you need to multiply the constant vector 4 and constant and apply it to emissive color

For creating walls and gate you need to create a material and import a png image .

And use the png image as texture sample and connect the (rgb) of texture sample to the emmisive color & connect the alpha value of texture sample to the opacity

The save it, go to the third person example map and create a plane or cube apply th material which you have created for the wall or gate

Thus, To Implementing various effects in material properties in Unreal Engine is implemented successfully.