Thai for "apply juice", probably correct but you may have to listen to someone saying it.
nam appen (narhm appben)
Nam = water
appen = apple
If you say nam incorrectly it means fermented meat.
Now to say "I am"
If you are talking to an older person say, "nou pben" ("nou" can mean mouse but you can use it to refer yourself to an older person, "ben" means to be)
If you are talking to a younger person, "Pea pben" ("pee", again I suggest you listen to voice overs because if you say "pea" in a different tone it means ghost, so you'd be saying "the ghost is apple juice")
"pea pben nam apben" (you can say apple juice as well its widely spread by the media so everyone knows it)