How do I extract sprites to make custom images?

[Skootroot]

I don't really know how to word the title but what I'm asking is basically how do I extract sprites to make something like this:

 

 

I made this using a transparent doom logo and a random doom texture in Kapwing. I want to know how to make things like this but with the game sprites (I know I can use SLAD3 but I have no idea how to use it for sprite work)

[Hitboi]

14 minutes ago, Reelvonic said:

you select sprites in slade and export as png

^ Simlar to this.

In Slade3, open the file you want to grab the graphic from (e.g. DOOM2.WAD and DOOM.WAD) > search for the graphic > right click the name of the graphic, click on "Graphic" > click on "Export as PNG" > place the PNG where you want.