Afraid to post photos on social media because I think someone might steal them

Hi Everyone! I am trying to start my own photography business. I would be advertising to do small weddings, private shoots, and such. But I will also be doing my own photos that include landscapes, cityscapes, nature and things like that.

I made myself a Facebook page because I figured with social media, i would be able to better advertise in my area. The only thing that is giving me pause is this. I have some really good shots and I want to put them on my page so people can actually see what I can do....but I am afraid of posting my stuff online because what if someone really likes my shots and steals them for their own? I know it's silly and I can't control someone copying and pasting my stuff. And I thought about using watermarks but I don't want them to take away from the actual photo.

Does anyone have any advice? I'd really appreciate the help. Thanks in advance everyone!