On this holiday, you have to practise the KET different parts of the exam using this online resource. You have to send me your final score when you've finished each part. Ask me if you have any problem or doubt.
https://www.examenglish.com/KET/index.html
And this is the link for the PET candidates:
https://www.examenglish.com/PET/pet_grammar.htm
Happy holidays!