If you’re playing through CurseForge, that’s where your screenshots will be saved through. Open CurseForge then move to the next step.
Click into the profile or modpack that the world was played in.
... button to the left of the
Play button. In the drop-down menu, click
A window will open that shows all the files in the instance you played. Find the
Screenshots folder and double click to open it. Within are all the screenshots you made in your worlds!