I would have selected the part to remove, with a path for example, then use Selection > From Path just to be sure to have a safe zone when you want to clone or copy/paste
We can clearly see that you did not have a safe zone or a good delimitation
Then you can just select some element from the background to insert safely, even resize them, without bleeding nor taking a risk to "touch" your main subject as it will be outside the selection, you can even do your "cloning" if you like to clone or whatever tool you like to use, as you will have a safe area because you cannot draw outside a selection
Or just by putting your copy/past below, you can even go faster for example the column, just stretch it until it fill all the way to the bottom (you can do a median blur afterward to smooth things out without bleeding, (same for the wooden wall, take an horizontal sample, copy/paste put it below the sofa in the layer stack, then stretch it downward... and it's almost done)
We can clearly see that you did not have a safe zone or a good delimitation
Then you can just select some element from the background to insert safely, even resize them, without bleeding nor taking a risk to "touch" your main subject as it will be outside the selection, you can even do your "cloning" if you like to clone or whatever tool you like to use, as you will have a safe area because you cannot draw outside a selection
Or just by putting your copy/past below, you can even go faster for example the column, just stretch it until it fill all the way to the bottom (you can do a median blur afterward to smooth things out without bleeding, (same for the wooden wall, take an horizontal sample, copy/paste put it below the sofa in the layer stack, then stretch it downward... and it's almost done)