DIY
Learn the History of Halloween Day should only be a thing for you one time. That makes it kinda weird as a special yearly day.
Unless you have a really bad memory.
No, I'm not going to tell you the history of the holiday here. That's what you have to go find out to celebrate this special day.
I will make it a little easier for you by giving you the link to the Wikipedia article here.
Next year on this date, you can read that article again (if it still exists) and pretend you didn't remember reading it the first time.
Now, if you think you actually know the history of Halloween already this year, that just means you're too much of a know-it-all and should go edit that article to further educate others who will go read it after you're done.
As to whether or not to actually celebrating Halloween, that choice is totally yours.
Boo!