I have been watching ean English series for two months.

Have you ever heard of “Extra”?

It is suitable for beginner levels.

The characters of the series are funny.

You can learn new words and improve listening skills (by watching it).

Nothing wrong with your original sentence, I just suggested adding this to add more flow to your sentences (because you never use 2nd person before this)

This is athe story of Bridget and Annie, who share a flat in London.

Bridget gets a letter from Argentina, and a new characters will be/come there soon.

"Come" would sound better than "be"

Enjoy watching !

I have been watching ethe English series, “Extra,” for two months.

Have you ever heard of “Extra”?

It is suitable for beginner levelanguage learners.

The characters ofin the series are funny.

You can learn new words and improve listening skills.

Instead of “words” you a say, “ vocabulary.”

ThisIt is a story ofabout Bridget and Annie who share a flat in London.

I have been watching ean English series for two months.

You always capitalize 'English.'

It is suitable for language learners who possess a beginner level.

Great job using the word suitable. You need a be a bit more specific here.

The characters ofin series are funny.

When speaking about characters in a movie, book, or series we use 'in' not 'of.'

This is a story ofe plot centers around Bridget and Annie who share a flat in London.

This just feels more like it comes from a native speaker. What you wrote was fine but felt like it was a beginner's level.

Enjoy watching !

There is never a space between a letter and a comma, full stop or exclamation point.