How; in what way — asking or indicating the manner or method something is done.
いかにして彼はその問題を解決したのか、詳しく聞きたい。
I want to hear in detail how he solved that problem.
政府は如何に政策を変えるつもりか、国民に説明するべきだ。
The government should explain to the public how it intends to change its policy.
料理は見た目も大事だが、如何に味を整えるかが肝心だ。
Appearance matters in cooking, but how you adjust the flavor is crucial.
How much; to what extent — asking or stating the degree/amount of something.
不安が如何に大きくても、まず落ち着いて対処することが大切だ。
No matter how great your anxiety is, it's important first to calm down and deal with it.
彼の努力が如何に報われたかは、結果を見ればわかる。
You can see how much his efforts were rewarded by looking at the results.
如何に忙しくても、健康は後回しにしてはいけない。
No matter how busy you are, you shouldn't put your health last.
However (much); no matter how — used to express concession or emphasis (as in 'no matter how...').
いかに努力しても、運がなければ成功しないこともある。
However much you try, sometimes you won't succeed without luck.
いかに名声があっても、人としての礼儀を失ってはならない。
No matter how famous you are, you must not lose basic courtesy as a person.
An archaic interjection meaning something like 'hey' or 'oi' — formerly used to call out or express surprise; now rare.
（古典文）『いかに、そなたは変わり果てたり』—古い文学で見られる表現。
(Classical) 'Oi, you have changed completely' — an expression seen in old literature.