Do you want alphabetical vertical or alphabetical pages?
If alphabetical vertical follow @MsVirgo87 instructions.
If you want Horizontal pages alphabetical you have to go to the Galaxy Store and download Good Lock app and then download the HomeUp app within the Good Lock app. Once those are downloaded, open the HomeUp module, turn it on. Then toggle on Homescreen . Open it, scroll down to horizontal scroll and toggle on. Your pages will now be in alphabetical order. There a lot of other excellent settings in there too.
