i think i got a virus in my i phone 7 plus

from two days i got notification from the calendar that i have event ( sex game) , which i never reserve such event and i never used the calendar before at any events!!! i delete it then i got the same the day after,

yesterday i found the phone said that it's updated and want the password to open, while it never been updated automatically, then after i open it , my facebook' timeline automatically post on one of my friends timeline as if i am writing on her timeline,

finally i open my apple ID then i discovered that my page said that this apple ID is signed in to two devices iphone 7 plus (my phone) and iphone 8 plus (not mine) i deleted the last one.

now i think i have a virus, i never thought that apple devices may got viruses, what should i do!!!