せんぱく is the standard on'yomi, with 舶 often becoming ぱく due to a sound change. 船 (セン) means ship, and 舶 (ハク) means large ship. せんふね uses the kun'yomi for 船, and せんべき/せんふく misread 舶. This is a general term for ships or vessels, often referring to larger boats used for transportation or fishing, implying a more formal or comprehensive term than just 'boat'.

せんぱくは標準的な音読みです。船は「ふね」、舶は「大型船」の意味。船全般、特に大型の船を指す公式な言葉です。せんふねは訓読みとの混同、せんふくは舶の誤読です。