Asexuality is a very simple concept, but it IS weird if you think about it. We're not heterosexual aka straight, we're asexual. But there are also people who don't think we should be counted as part of the LGBT+ community because we aren't bisexual, homosexual, and so forth (despite that being covered by the plus sign). There are even instances of people who say that we're broken because we're not sexually attracted to people!
We're not broken.
A simple way to think of asexuality is like this: we're just not feeling it. Like how you don't feel attracted to particular people even if they're the gender you're attracted to, we just don't find people sexually attractive. We don't really find things sexy.
We can still experience romantic attraction, so we can still date. We can still experience aesthetic attraction, so we can still find people beautiful or handsome or cute. We can still experience familial love, so we can still love our parents and siblings and other family members. We can still experience friendship.
Love still exists for us, it's just not the same as everyone else.
Sexuality is a spectrum - thus the term "asexual spectrum" or "aromantic spectrum", often shortened to "a-spec", which helps for people who don't feel entirely asexual, such as grey asexuals or demisexuals. They sometimes experience sexual attraction, but it's not as easy as saying "oh, I'm gay" or "oh, I'm bi" for them.
Honestly, the fact that all of these labels exist is wonderful! It helps us figure ourselves out and it's great for us to have words to describe how we feel, to help us connect to other people like us.