Hey @AshhhDTD - you definitely can’t I’m afraid. The reason is that the anus is almost like a vacuum, and will suck up anything that does not have a flared base. Secondly, if that happens you could cause serious injury as the anus is not a “dead end” as such and connects to your rectum and large intestine.
I would really recommend only using toys that are specifically designed for anal play. Even then, it’s really important to check that it has a flared base which is wider than largest part of the toy.
Hope that helps, exploring anal play can be confusing when starting out so it’s good to reach out and ask. Just to reiterate: these should categorically not be used for anal play.
You should be okay just starting out with a small beginners plug (I’d recommend a t-base one to start with, particularly for extended wear, and silicone to start with as it’s a bit more flexible). Remember lots of lube, and before you go to a plug explore using fingers and just take it slow. You can then start to increase the time you have it in, but go at your own pace and don’t try to rush anything.