Questions & Answers about Non voglio essere egoista.
Since egoista ends in -a, does that mean the speaker is a woman?
Not necessarily! Adjectives and nouns ending in -ista (like egoista, ottimista, or turista) are identical for both masculine and feminine in the singular. A man or a woman would use this exact same sentence.
How do you make egoista plural if it's the same for both genders in the singular?
Why isn't there a preposition between voglio and essere to mean "to be"?
Because volere (to want) is a modal verb, just like potere (can/to be able to) and dovere (must/to have to). When you use a modal verb directly before another verb in its dictionary form (the infinitive, like essere), you never put a preposition in between them.