The acronym for these experiences, LGBTQ+ is often used as a short hand to describe these communities, but it should not be mistaken as being an absolute or exclusive rule for what it means to be queer. The acronym hasn't always been LGBTQ, LGBT, or even GLBT. There was an era when the inclusion of lesbians, i.e. gay and lesbian, was considered not only radical but overly politically correct!
It's important to remember in the study of queerness that queerness has evolved and will continue to do so, and while this framework might be helpful right now to some people, it should never feel confining or be assumed to be the only way to be queer. As long as it’s consensual and outside of traditional cis-hetero understandings of interpersonal relationships, it's queer.
It is also important to remember that the LGB and T roles are descriptive rather than prescriptive. Even within the established communities there is a lot of cross over, lesbians can be bi, trans people can be straight, and gay people can be queer or ace. With that in mind, the pages linked down below will help you better understand how other people, and maybe even yourself, experience the world as queer people.