宇 is a Chinese hanzi, listed here under the keyword “house”. It is built from 宀 (roof) and 于 (in). It appears as a component in 1 other character in this index.
On KumiJi Glyph Explorer, open the parts search and type “roof” + “in”. 宇 is among the results, together with every other character containing the same shapes.
Open 宇 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.