Here are some:

People will constantly tell you how attractive you are:

Ok this is just wrong. I mean sure if you're attractive you'll probably receive some compliments, but it's not like people will just walk up and tell you that. I mean think about it. If you saw someone whos attractive just walking down the street would you just walk up and tell them that? It takes a lot of nerve to do something like that, not to mention it can come off as creepy. Usually people will talk about it behind your back rather than to your face, or if people do they will usually be of the same gender since it isn't as intimidating that way. You may have some people of the opposite gender tell you you're attractive but those wont be the majority.

Everyone stares at you:

Attractive people will definitely receive much more stares than average people but it's not like everyone will just openly stare at them 24/7. This is especially true if it's in a crowded area with many people. When people are walking down the street or whatever they're usually just minding their own business and aren't busy staring at everyones faces. If people do stare at you the majority of the time it will be when they think you aren't looking to avoid coming off as creepy. Or they might look at you for a brief moment but quickly look away as to not make it obvious.

You'll constantly be asked out and rarely be single:

Again no! Most people will try to let you know they like you through subtle cues and then move on from there.

Also you can be single your whole life and still be attractive. Let's say you're introverted and dont approach people often. This will be especially hard to find a date as many people are intimated of attractive people and get nervous to approach them, so you usually have to be the one to make the first move. Attractive people also often have higher standards so they might think most people aren't up to their league. Also if you have a bad personality or are a douchebag no amount of good looks are gonna make people want you. It can also just be that you dont know many people or the ones you do are already taken.

You don't get any matches on dating profiles:

Ok if you don't get any matches than its likely that you arent very attracitve in the pics you're using. However some people simply aren't photogenic and are way better in real life. It could also be that you have a boring profile or something about rubs people the wrong way. For example if you say "I'm not interested in a relationship, I just want to fuck" many wouldnt swipe since it seems like you're just interested in sex and nothing else.

But these are just some common misconceptions I've seen. Do you have any other you'd add?