Free grammar and language tests with answers

B2 level

https://englishpracticetest.net/practice-english-grammar-tests-for-b2-with-answer/

https://www.esl-lounge.com/student/first-certificate-multiple-choice-cloze.php

https://test-english.com/use-of-english/b2/b2-english-test-2-multiple-choice-questions/

https://engxam.com/handbook/5-free-practice-tests-b2-first-fce/#b2-first-fce-practice-online-use-of-english-tests-online-pdf

https://www.examenglish.com/FCE/fce_grammar.htm

C1 level

https://englishpracticetest.net/practice-english-grammar-tests-for-c1-with-answer/

https://www.esl-lounge.com/student/advanced-multiple-choice-cloze.php

https://engxam.com/handbook/practice-tests-c1-advanced-cae/

https://www.examenglish.com/CEFR/C1.htm