oh nah definitely have actual physical bubbles; if you have the text without a bubble holding it youll have all sorts of problems when it comes to legibility. bubbles enclose a piece of text and stop it from being lost in the background of your comic.
id recommend reading up on how to letter though, and make your texts rounder. for example:
id recommend
reading up on how
to letter though, and
make your texts
rounder.
except, like, not left aligned like it is there. break up your text to make a rounder shape, or taller if you need it that shape to fit around the image.