False. You are very limited to your time, social connections, geography, ect.
If I am "someone"
And "having sex with" is anything
And Rihanna is "anyone"
And right now counts as "any time"
Then your logic would follow that I can have sex with Rihanna right now if I wanted to.
But, this is clearly not the case. I do not know her, and even if she was a willing participant that doesn't change the fact that she almost certainly does not not live anywhere remotely close to me.
There's also some things a person can not do because it is outside of their authority. For example, I (someone) can not award (do anything) my beloved grandmother (anyone) a Nobel Prize because I am in no position to do so.