In English, both by and through mean "through", but they have certain differences in their use.
1.by means "by some way or method".
by is often used to mean "by some means or method" to achieve the purpose. For example:
i got here by bus.(I got here by bus.) ）
i learned english by practicing.(I learned English through practice.) ）
2.through means "through somewhere or something".
Through is often used to mean "through one place or something" to get to another. For example:
i walked through the park.(I walk through the park.) ）
i can see the stars through the window.(I can see the stars through the window.) ）
3.The difference between by and through
The differences between by and through are mainly reflected in the following aspects:
By focuses on denoting "by a certain way or method", whereas through focuses on denoting "through somewhere or something".
BY is usually used to denote the means of an action or behavior, whereas through is usually used to denote the path of an action or behavior.
By can be paired with some nouns or verbs to indicate a specific way or method, such as: by bus, by car, by walking, by working hard, etc. Through can also be paired with some nouns or verbs to indicate a specific path, for example: through the park, through the window, through the crowd, etc.
In practice, by and through are sometimes interchangeable, but in some cases, their use is not interchangeable. For example, when expressing "through effort", you can only use by, not through.