The words floe, flow sound the same but have different meanings and spellings. Why do floe, flow sound the same even though they are completely different words?
The answer is simple: floe, flow are homophones of the English language.
An ice floe.
A segment that has separated from such an ice mass.
To move or run smoothly with unbroken continuity, as in the manner characteristic of a fluid.
To issue in a stream; pour forth: Sap flowed from the gash in the tree.
To circulate, as the blood in the body.
To move with a continual shifting of the component particles: wheat flowing into the bin; traffic flowing through the tunnel.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.