You can use the word “how” to ask questions in English. These are called “how questions”.[1]https://www.engvid.com/4-types-of-how-questions-in-english/
Similar to “Wh-“ questions, you can ask:
How + modal verb
For example:
- How can you sing so well?
- How can you know so many languages?
- How can I get there?
How + verb (any tense)
- How did she do that?
- How are we going to get there?
- How is it outside?
However, there are 4 specific cases where you only use “how” to ask questions.
Adjective
“How” can be used with adjectives.
How + adjective
For example:
- How old are you?
- How hot is it outside?
- How difficult is the test?
Adverb
“How” can be used with adverbs.
How + adverb
For example:
- How quickly can you run?
- How well can she cook?
- How often do you work out?
Plural Countable Noun
How questions can be used with plural countable nouns.
How + many + plural countable noun
For example:
- How many dogs do you have?
- How many people are in the school?
- How many things did she buy?
Uncountable Noun
“How” can be used with uncountable nouns.
How + much + uncountable noun
For example:
- How much time do we have left?
- How much water is in the bucket?
- How much English do I need to know?
References