Hi @Deb ,
Welcome to our forum!
Based on my research, i got the same result as yours. I'm afraid that the "Quick Parts" menu is not available in New Outlook preview. If you need to use this function, it's suggested that you could turn off New Outlook button to switch to Legacy Outlook.
Please kindly understand that many functions of our current products are designed and upgraded according to customer feedback. At present, what I can do for you is to submit feedback for your request and I have post here. It's suggested that you could vote for it and you can also post your suggestions on that website. Hope Microsoft will notice this in the future. Thank you for your understanding and support!
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