Are you trying to make a , or set a solid background for a picture? Once I know, I can give you the exact steps. Features - 2021 - SOLIDWORKS Design Help
Based on your query, it seems you are working with a and want to create a solid feature, likely within a CAD (Computer-Aided Design) environment like SOLIDWORKS, or perhaps you are referring to a solid, non-transparent background. 1234567.PNG
To create a "solid feature," you are likely looking to turn a 2D sketch into a 3D part using tools like Extruded Boss/Base , Revolved Boss/Base , or Sweep . Are you trying to make a , or