Hi Pragya Pandey,
For this, create a microflow and need to check the date field using the decision activity that is date < [%CurrentDateTime%]. And change the object to closed for true condition, and set object as open for false condition.
And return the object.
Hope this will help you!
using same solution mentioned by @aishwarya but with a nanoflow is better for your performance.
this can be used on change of the date field and you don’t need to commit. in a nanoflow you don’t even need to refresh the object.