Talk to Grillby.

You decide to walk over to the orange flame person. After getting a bit closer he seems to notice you, putting the rag away under the counter and wiping his hands clean. Clean of what, you aren't sure, but you continue approaching him anyway. When you get up to the counter the flame person seems to notice you, so he nods his head in acknowledgement, before pointing to something on his shirt. You lean in a bit closer to see what he is pointing at, and realize that it's a nametag. The nametag says, "Grillby," so his name must be Grillby. The nametag also says that he is the owner. You nod your own head in acknowledgement, and tell Grillby that your name is Vessel. If he has an opinion of your name, Grillby's lack of facial features make it very hard to tell.

Just as the silence between the two of you is starting to get really awkward, you notice a hiring sign leaning against the wall behind Grillby. You already have some money, though it couldn't hurt to earn more cash. Aside from that, you could order something to drink and try to strike a conversation with Grillby. It might be rather difficult, due to how opposed to speaking Grillby seems to be.