Update mid 2011 iMac to High Sierra

Hi, I can't find High Sierra on my 2011 iMac's Apple Store. I searched "macOS high sierra" but no results. There is "macOS Monterey" but the App Store it couldn't complete my purchase because my device doesn't support this purchase/software/etc... Is there another way for me to update my 2011 iMac?

Hi! I can access the macOS High Sierra now after I restarted my iMac and opened the link using Safari. I'm downloading the software, hopefully it will turn out alright!

After I update to High Sierra, can I update to 10.15? I want to install Microsoft Word and Outlook but they require 10.15 or later.

Thank you so much for your help!

Van

Thank you so much! I wanted to press "Helpful" and "Solved my problem" but I can't seem to press "Helpful" now that I pressed "Solved my problem". Just would like you to know that I am very grateful for your time and help. Have a great week ahead!

By the way, may I trouble you one last time? How can I install Microsoft Word and Outlook on iMac mid 2011 now updated to High Sierra? If not, is there a way for me to use the iMac as my second display? I have a Macbook Air 2020 (13 inch).

I installed Duet Display on both my MacBook and iMac and on them it says “connected” (mirroring) but I don’t know how to switch the mirror mode or extended mode in. They still are 2 different devices without connection to one another. Have you used Duet Display before?

Yes and it took me to App Store app. :(

I'm running on Sierra.

OMG thank you so much! You have an answer for all my problems!!! I am setting it up and from the look of things, it may work as I have hoped!