Watching movies and series in the original language can be a great way to improve your language skills and learn new vocabulary. By watching content in the original language, you are exposed to authentic language usage and can see how the language is used in a natural and contextualized way. This can help you to better understand the language and become more proficient in using it.
However, if you are just starting to learn English or if your language skills are not yet advanced, it may be more difficult to understand the content if you watch it in the original language. In this case, you may find it more helpful to watch content in English with subtitles in your native language, or to watch content that has been dubbed in your native language. This can help you to follow the story and understand the dialogue more easily, while still getting exposure to the English language.
Ultimately, the best approach for you will depend on your language level and your personal learning goals. If you are comfortable with the original language and feel that it is helping you to improve your language skills, then watching movies and series in the original language can be a great way to learn. If you are just starting to learn English or if you find it difficult to understand the original language, then watching content with subtitles or dubbed in your native language may be more helpful.