So I purchased an ESC/POS thermal receipt printer that shows up on my machine as a "Texas Instruments Generic Bulk Device". When I try to print it prints out the postscript commands instead of the actual content.
My question is, is there a way to connect to is (app, console, etc) and either print a document or stuff line by line?
You need a print driver for the printer, the vendor should have supplied this to you. Almost certainly this is not a PostScript printer. PostScript for such a printer would be insanely over-specified.
However I imagine the printer accepts text, try just sending that.