いかに
いかに · ikani · JLPT N1 · adverb
how
如何 = like + what; いかに asks "like what?", meaning how or in what way
The kanji 如 means like or as, and 何 means what. Together they ask in what manner, which is the sense of how. It is a formal, literary word, so it appears more often in writing than in everyday speech.