Since both 还是 and 或者 can be translated as ‘or’ in English, learners who are English speakers should pay special attention to the distinction between these two words.
Qǐng nǐ gěi wǒ yī bēi chá huò zhě kā fēi。
Please give me (either) a cup of tea or a cup of coffee.
When 或者 is used in a question, it is an affirmative–negative question or a question with the modal particle 吗.
王：我很渴， 想喝一点饮料。有没有茶或者汽水？(= 有茶或者汽水吗？)
Wáng ：wǒ hěn kě， xiǎng hē yī diǎn yǐn liào。yǒu méi yǒu chá huò zhě qì shuǐ ？(= Yǒu chá huò zhě qì shuǐ ma？)
Wang: I am thirsty; I want to drink something. Is there tea or soda?
Lǐ：Yǒu。Yào qì shuǐ hái shì yào chá？
Li: Yes. Do you want soda or tea?
(This is an alternative question offering choices.)
 Yip, P. C., Rimmington, D., Xiaoming, Z., & Henson, R. (2009). Basic Chinese: a grammar and workbook. Taylor & Francis.