Hi Kumar,
These processing steps are separate because sometimes you might want to alter the order. That said, here are my recommendations for normal processing, with the strongest recommendations first:
I would not worry about choosing E0 or normalization until after merging.
If you need to align scans, do that before merging. But see below on "re-binning".
If you need to de-glitch multiple scans, first try to figure out why and what energy values need to be de-glitched. If these values are not consistent across scans, it may indicate that your sample is causing the glitches, which is not really consistent with "amorphous anatase". If the glitches are consistent and at nearly the same energies, you probably want to de-glitch before merging.
Are you certain you need to re-bin the data? If so, you should probably consult with beamline scientists or people familiar with the data collection on whether that should be done before energy alignment. Some data collection systems that generate data that needs rebinning probably imply that you should *not re-align* at all, but trust the energy values.