Your mail can go missing from your inbox because of filters or forwarding, or because of POP and IMAP settings in your other mail systems. Your mail server or email systems could also be downloading and saving local copies of your messages and deleting them from Gmail.
Where do I find my Inbox?
Inbox is located in the Message List. Emails open in the Reading Pane. The ribbon gives you more options to organize emails.
How do I check my email inbox on my phone?
https://www.youtube.com/watch?v=H4hbQtW7yyc
How do I find my inbox in Gmail?
To view your Inbox, open https://mail.google.com or https://www.gmail.com. For details, questions or follow-up, please post in the Gmail help community at https://support.google.com/mail/community. To view your Inbox, open https://mail.google.com or https://www.gmail.com.11 Sept 2019