Shem is named first in Genesis’s list of Noah’s sons who entered the Ark.
Genesis identifies Noah’s sons as Shem, Ham, and Japheth, and says that they entered the Ark with their wives. Shem is listed first in the relevant passage. All three sons survive the Flood with Noah and their mother, although Genesis later gives them different roles in the genealogical traditions that follow.
The order of names is easy to confuse because another passage, Genesis 10, presents the sons in a different order—Shem, Ham, and Japheth in many translations, with the surrounding genealogies drawing attention to different descendants. The important point for this question is the explicit family listing connected with Noah and the Ark.
Canaan is not one of Noah’s sons. Canaan is identified as a son of Ham in the later account of Noah’s drunkenness and its aftermath. This family relationship explains why Canaan sometimes appears near Noah’s story while still being a different generation.