界 is a Japanese kanji written with 9 strokes, listed here under the keyword “world”. It is built from 田 (rice field) and 介 (jammed in). In Remembering the Kanji by James W. Heisig it is frame 266.
On KumiJi Glyph Explorer, open the parts search and type “rice field” + “jammed in”. 界 is among the results, together with every other character containing the same shapes.
Open 界 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.