Take a look at the custom string widget: https://marketplace.mendix.com/link/component/1426

For sending a full object back for 1 parameter isn’t recommended. 
The above widget can send back the text for you. 

Hey Venu, 

The currentuser (when logged in) should already have this information without needing to retrieve it from DB. 
To get it out just make a variable (reference screenshot):

Your XPath currently says: Get All Accounts that have the same last login as my current user. 
If you want to retrieve yourself from DB go with [id = $currentUser]

However, this should not have to be the case as the above variable should give you the information without needing to do this. 

Created a microflow and returning as Date and Time. But how do I retrieve that in a page. Please let me know

Created a microflow and returning as Date and Time. But how do I retrieve that in a page. Please let me know

Able to use CustomString widget but it is retrieving the current login time. I want to retrieve the previous login date and time(for example, I logged in at 7/22/2021 9:50 AM for the first time and 7/22/2021 9:55 AM second time then I should see the first login time).

Have you replicated the issue if yes provide how did you achieved 

Thanks in advance