Hi @Oskarkuus,
Do you want to get events that will start on today from SharePoint Calendar list then post them on Microsoft Teams?
Please try the following flow configuration. I have made a test with it and it works fine.
Add a Condition and use the following code to filter events that will start on today.
@equals(formatDateTime(items('Apply_to_each')?['EventDate'], 'yyyy-MM-dd'), formatDateTime(utcnow(), 'yyyy-MM-dd'))
Images for your rerference:


Besides, to automate the flow each morning, please use the trigger Recurrence and set the frequency and interval according to your needs. Please try it and feel free reply if you need more help.
Best regards,
Mabel Mao