There are multiple posts being circulated claiming that due to pandemic Olympics couldn’t happen this year. As a result the organizers couldn’t store the fire works for next year, they gave a go ahead to use this now.
WOW! This is so cool. You'll want your sound on for this one.#Tokyo2020 had their fireworks all ready, but since they can't store them til next year they decided to light 'em up this week.
— Rachel Notley (@RachelNotley) August 14, 2020
Verdict:- Fake News
Explanation:- No these videos are not from Japan Olympics. A similar video was published a few years ago.
This website can be used to create fire works simulation.