Hi @Mark Levy ,
Welcome to our forum!
First, spell check and autocorrect, I can't find anywhere to make changes.
Based on my research, Autocorrect option is not available in New Outlook for Windows. And i found the following option in Settings which can be used to help us edit better. If you truly need to the autocorrect option, i'm afraid that you need to turn New Outlook button to switch to Legacy Outlook.
Please kindly understand that many functions are not designed at present. To get this feature more quickly, I have found a post in feedback collection website and you could vote for it. Many features of our current products are designed and upgraded based on customers’ feedback. You can also make suggestions on that website and hope Microsoft will notice this in the future.
Second, junk mail settings, I've started receiving a lot of junk mail to my inbox and I can't find where to make changes.
As i know, many of the features in the New Outlook for Windows work the same or similarly as Outlook on the web. Please refer to this article to apply the related Junk setting:
Filter junk email and spam in Outlook
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