Read the readme files and check if there is any merge-related thing written there.
Also, check the readme files and see if there are any manual steps for applying those patches.
If you see any manuel steps in a patch's read me file, dont merge it. Apply it seperately by following its readme file
If you dont see any manuel steps, I suggest you to merge the prereqs with the main patches.
So if you have 3 main patches, each consist of prereqs, then merge each main patch with its prereqs and apply those 3 merged patches one by one.
Localization patches are sensitive.. Most of them have manual steps, and they may get errors. So first test your patch application in a TEST instance, then go to Live.