how can i use "还是“ ”或者“

The main difference is that generally 还是 is used in questions, and 或者 is used in statements. Translations of 或者 often involve ‘either’, whereas translations of 还是 are often just ‘or’.

In a question, you use 還是 In a satement you use 或者
你喜歡蘋果還是梨子?
你可以問他或者問我

还是 o para preguntas:你吃梨还是苹果？
或者 o para oraciones afirmativas: 今晚吃中餐或者西餐。

You use 还是 when you are asking a question that means "is it this or that?"

You use 或者 in a statement to indicate you either do/have this or that.

还是 IS used to Ask
Zhe shi ni de mama hai shi ni de jiejie?
或者 IS used In statment not question

Please check this point, 还是 vs 或者
https://www.cchatty.com/grammar/10365

"还是“表示疑问，多用在疑问句；”或者“表示选择，强调选择。

还是用于选择问句。
或者用于肯定句。

你要喝咖啡还是喝茶？（ 问句）
我喝咖啡或者茶都可以。（ 肯定句）

或者是用在兩項以上可供選擇的情況或條件的敘述句