Help me in grammar

when we want to combine into one questio “of course in grammar” what sould we do?
shall i use comma between these two questions?
at the end we use (? or . )
would you mind if you explain that with simple example…
thank you

I muse upon that nobody understood what you had in mind…

may be i asked that wrongly when i have these 2 sentences
what does she have? and" tell me " i want to ask using these 2 questions together
so it became (tell me what she has) so any punctuation should i use here or not
and what we call this kind of grammar?

Suggestion: 1. Tell me what she has. 2. What does she have? Tell me.

Grammar: 1. Imperative sentences give instructions. 2. Interrogative sentences ask questions. Some interrogative sentences begin with the following words: Who, what, when, where, why, how.