please confirm if i am calculating correctly:)

Hi,

i will be arriving to Japan Kansai international airport on the 20th of January 2020 at 9:40pm and leaving Japan from Kansai International airport on 10th February 2020 at 10:00pm

if i buy the 21 day JR pass and activate it on arrival, will it still be valid for me to be able to make it back to the airport on the 10th of February or am i falling a day short?

also could you tell me how to get to mt. fuji from tokyo using JR pass? which stations are best to get off at etc. I have read through your blogs and found a link but it took me back to the page to purchase the jr pass haha

thanks heaps and cant wait to explore this amazing country!