Hi @Reo Yamagishi (山岸 玲央) ,
Welcome to our forum!
Please understand that only English is supported in this forum. I used machine translation for your post, please forgive me for any misunderstandings.
I understand that you want to create a link to access Outlook for Web, where exactly do you want to access?
As i know, we can only access the default folders in Outlook for web by clicking a fixed link, such as Sent Items folder, you just need to click: https://outlook.office.com/mail/sentitems
In addition, i notice that you want to generate a link with Power Automate, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. It's suggested that you could post your issue in dedicated forum for Power Automate for more professional advice.
Hope to help you!
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