Not really sure about what you are intentioned to do, but if it's something like this...
Attachment:
photography_by_shivamart1-dc95lw0_witrh-a-rose-on-top.jpg [ 215.74 KiB | Viewed 2607 times ]
it could be obtained by:
- opening the BG image
- opening the image you want to override
- add transparency on the latter (layer>transparency>add alpha channel)
- remove unwanted part (in this case all around the rose) using the eraser tool and/or the select by color/hue and cut)
- move that rose on top of the BG (copy, and past as a layer)
- reducing opacity of the top layer
Attachment:
photography_by_shivamart1-dc95lw0_witrh-a-rose-on-top.jpg [ 215.74 KiB | Viewed 2607 times ]
Attachment:
fiore-rosa-2-scaled.jpg [ 61.62 KiB | Viewed 2607 times ]