– Topic plausible? No -> Spam/Phishing/Malware
– Sender plausible? No -> Spam/Phishing/Malware
– Does the subject match the sender? No -> Spam/Phishing/Malware

Other points that may indicate spam/phishing/malware:
– Does the language match the topic/sender? German/English?
– Does the salutation fit? General or personal?
– Does the text look as if it has been translated by an old translator?
– Are there threats?
– Is there a requirement to register somewhere?
– Are there links in the text?
Hover over the link, do not click

Does it indicate a meaningful address?
Does the address match the sender address?

See also here: https://itsecurity.ethz.ch/en/#/spot_phishing_emails

Outlook has a spam folder. Its name is Junk E-Mail. However, not many mails should end up there, because we have a central mail filter. Its name is MailCleaner and it regularly sends you information about mails that have been retained. See: https://www.ethz.ch/services/de/it-services/katalog/email-kalender/mailfilterung.html and https://mailcleaner.ethz.ch/