線 is a Japanese kanji written with 15 strokes, listed here under the keyword “line”. It is built from 糸 (thread) and 泉 (spring). In Remembering the Kanji by James W. Heisig it is frame 1438.
On KumiJi Glyph Explorer, open the parts search and type “thread” + “spring”. 線 is among the results, together with every other character containing the same shapes.
Open 線 in the interactive kanji search
to expand every part down to its smallest pieces, add your own names and mnemonic stories,
or search for other characters by their parts.