Access does not provide a means to execute a SQL script
you would use vba.
you could just send an 'update' db - written instructions would just be - open this db
write vba code in a module to execute the three queries and exit the database and have the sub activated by an autoexec macro - or in a form if you want to show progress
code would be something like (not checked for syntax)
Code:
Public Sub doUpdate()
dim db as database
set db=opendatabase("existing backend")
db.execute ("create table....")
db.execute("create index....")
db.execute("alter table...") - note this can be done as part of the create table sql
db.close
msgbox "backend updated"
docmd.quit
end sub