What would traveling be like if the Earth were as large as the Sun?

Rather as several others have mentioned the Earth would have ignited as star under the force of gravity. Due to the “surface” temperatures, you’d get to experience travel as a plasma or a gas cloud.

As you moved along an essentially turbulent ocean of similar material you would notice (if somehow you retained consciousness) that while being jumbled along that the surrounding photons were constantly blowing little bits of yourself away into the space around your star. Things would be very bright and very warm. You would continue this way until you were blown away or caught in solar flare where the same would occur, only more explosively.