Here are some websites of English for B1 level:

Grammar tests and quizes click: Grammar

180 pages of English grammar click: Grammar2

Lots of grammar and words click: Grammar3

Many English activities click: EnglishCafe

English lessons, exercises and Games click: Lessons

Many activities for English students click: AllEnglish

Listen and repeat English click: Speaking

Read and listen to English click: ReadListen

Good pronuciation site: Pronouce

English activities and tests click: ActiveEnglish

Learn English with the BBC click: BBCenglish

Try 3 different English levels click: EasyEnglish

Writing, reading, spelling and more click: Skillswise

Do the "medium" listening tests click: Listening
 
Listen to slow and fast English click: Listening2

Over 1000 lessons for listening click: Listening3

20 full English lessons click: Allenglish

Video lessons with a teacher click: VideoTeacher

Many video lessons for your level click: VideosB1

Many games for learning English click: Games