Here you can review the simple future tenses theory and here the futures simple and continuous.

Online activities

https://test-english.com/grammar-points/b1/future-forms/

https://www.engblocks.com/grammar/exercises/future-forms-will-be-going-to-present-continuous/future-forms-will-be-going-to-present-continuous-exercise-1/

https://www.tolearnenglish.com/exercises/exercise-english-2/exercise-english-6874.php

 https://english.linolia.com/en/grammar/tense-comparison/future-tenses/exercises

FUTURE CONTINUOUS

https://www.perfect-english-grammar.com/future-continuous-exercise-1.html

ALL

https://english.lingolia.com/en/grammar/tense-comparison/future-tenses/exercises