Your original question was in regards to not being able to find the "Studio" button within your course navigation. Per this Guide, the "Studio" course navigation button is only available to instructors...not to students.
How do I use Canvas Studio through the Course Navigation Menu as an instructor? (specifically the Note in the blue box).
However, the "Studio" icon found within the global navigation menu on the left hand side of your Canvas environment is available to both instructors and students.
Also, on a completely separate note, I'm not sure why you changed the title and body of this message. Even though you've now indicated to disregard this, you had a response from Kelley L. Meeusen before editing the question. It's a good idea to keep the title/body of your message originally what it was...because you never know when someone else might have the same kind of question...and so your question and any feedback might be of help to them. I hope this makes sense, Becky.
Also, I hope the above information on the "Studio" button has helped to answer your original question.
I will almost 100% guarantee that it just needs to be dragged up to the "enabled" list of Navigation items under Settings. This guide will help How do I manage Course Navigation links?
Let me know,
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