There is no specific word "sweam" in English. It is possible that you intended to write "swim", which is the correct verb form.
The word "swim" originated from the Old English word "swimman", which meant "to move or float on or in water" or "to bathe oneself". The Old English word was derived from the Proto-Germanic word *swemmaną, which carried a similar meaning. This Proto-Germanic term is believed to have been influenced by the Proto-Indo-European root *swem-, meaning "to move rapidly or glide".
Over time, "swim" has remained relatively unchanged in its spelling and pronunciation, with minor shifts in phonetics and inflection.