As far as I know, Filemaker supports AppleScript. Bridge supports JavaScript, so you have to mix both languages. How to insert keywords in Bridge was discussed several times in this forum – just search the forum and you'll find examples.
WRT Filemaker I can't tell you something definite, because I don't have a copy of it installed and can't peep into its dictionary, but I think there should be some example scripts that do something close to what you need.
I'm sure it's possible, but it would be a difficult task for a beginner.
Kasyan