I want to show the number of logged in user's "Tasks" using "

I want to show the number of logged in user's "Tasks" using "Web content with Dynamic data" channel. I searched for expressions but couldn't find. is there any way to get number of tasks for a user and show it on a page? for example when a user launches the apps he can see a channel displaying something like this :

Dear [Lily], You have 10 tasks and 7 alerts....

OriginalPostID-87183

OriginalPostID-87183

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