bisexual
The word 'bisexuell' in German is used to describe a person who is attracted to both men and women. It is the equivalent of the English term 'bisexual'. In German, as in English, this term is used to describe sexual orientation and is not limited to romantic relationships, but can also include emotional and/or physical attraction.
I am bisexual.
This sentence is a self-declaration of one's sexual orientation as being bisexual. In German, 'ich bin' translates as 'I am', and 'bisexuell' is the direct equivalent of 'bisexual' in English.
He finds out she is bisexual.
This sentence tells a situation of a person (he) discovering the sexual orientation of another person (she) as being bisexual. Here, 'er findet heraus' translates as 'he finds out', 'dass' as 'that', 'sie' as 'she', 'ist' as 'is', and 'bisexuell' is 'bisexual'.
Being bisexual is completely normal.
In this sentence, the speaker defends and normalizes bisexuality. 'Bisexuell zu sein' translates as 'being bisexual', 'ist' as 'is', 'völlig' as 'completely', and 'normal' is the same in English.