Job interview I need advice!!

Hey yall! I am a young mommy to a baby girl and me and her daddy live together and are engaged. Were off one income (his) so I started getting a little stir crazy being a stay at home mommy ( I applaud any mommy who is a stay at home mom it is hard work!!) Well I got my first job interview soon being a sales associate at a department store any advice!? (Like what to wear, how to Answer questions, how to be confident, etc)

Side note: my man is being very unsupportive so I have come to the ladies of glow for support!!