How do I set the purchasing of lottery into everyday event in calendar?

I think this is a hidden event, you can't delete it and you can't add it more often.

@crocobaura is correct, this is a hidden event, not something we have control of.

The lottery event can be cancelled on the calendar before the day of the event. I never let my Sims take part in it because I got tired of newborns winning. Or random Sims that can't be tracked down and only exist in the game's imagination. The only advice can I give is to search for a mod for the lottery event. There are many mod creators out there that have random holiday traditions mods, I use many of them myself, and those add many fun things for your Sims to do on holidays. https://forums.thesims.com/en_US/categories/mods this link is to the mods section where they might be able to help you find the lottery tradition. :)

@bootsguy Here is another link to a mod creator. I use a lot of her holiday traditions, but I don't remember seeing one for the Lottery. Good luck in your search. https://kiarasims4mods.net/traditions/

I think I had a ghost cat or something win the lottery before. :D

Haven't had any foxes win the lottery yet though. :p

I'm not sure if you are still looking for a solution but I this is the mod I use:
Make Hidden Holiday Traditions Selectable by EP1CxEMAN08 @ MTS updated: 14th Mar 2023

@SimplyJen I just downloaded the mod since I can have the freedom to set this event in my Sims calendar. Thank you!

Indeed a hidden holiday tradition without mods. Get ready to have every other sim rich even the pets but never your own sims. :D

I've had one win once - and maybe only once lol

I have never once had a sim of mine win the Lottery. Feels very true to life if I'm honest. :D