肆 is a Chinese hanzi, listed here under the keyword “indulge”. It is built from 镸 (long) and 聿 (writing brush). It appears as a component in 1 other character in this index.
On KumiJi Glyph Explorer, open the parts search and type “long” + “writing brush”. 肆 is among the results, together with every other character containing the same shapes.
Open 肆 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.