SCP Foundation

My plan for this SCP is where it is a pot of soil that if you're gonna talk about it, you're gonna say the opposite for it. Then I want it to evolve into that the people who are exposed to it, do the opposite of what they do (security guards loiter in bars away from the facility, researchers continually redact important articles, like the containment procedures, and maybe the Foundation destroys the SCP). I dunno about this though. Would like your take on this

that if you're gonna talk about it, you're gonna say the opposite for it.

So what happens if someone intentionally says the opposite of it? Do they then just say things normally?

Then I want it to evolve into that the people who are exposed to it, do the opposite of what they do

This is pretty commonly seen as a premise, especially for "opposite day" based SCPs. Typically it doesn't really work because a lot of actions don't really have objective opposites. Also, the compulsion effect is pretty overdone. Take a look at the articles tagged with "compulsion". Furthermore, an SCP object's effect forcing someone to do something tends to be a bit of a lame narrative, since things are more interesting if there's a struggle involved, and/or if the people instead do terrible things of their own volition rather than just because the author needs them to for the story to work. Consider reading through the further discussion on the narrative issues of compulsion and addiction effects.

I personally recommend trying something else for your beginning drafts.