Hello,I have a Scenario Here,what can be done here?

I have a User, Who will leave the organization tomorrow. User is basically a manager and there are 15 users below him.
Now when this user leaves the organization i would generally inactivate the User.
But now my concern is if I inactivate this user What happens to the Role hierarchy, the assignment rules, Approval processes, the records created by him and records to which he is the default owner like leads and cases. And what would be best possible solution to keep this application intact and running ?

Any Suggestion would be appreciable.
Thanks in Advance!!

I am stuck at challenge 2 because I am not able to select this option

hi all,

I urgently need to edit/delete a post made by me on this discussion forum...But its not allowing me to do so and pops up
saying that 'you cant delete this question as others are interested in it'.
There are no likes and no comments on it still i am unable  to delete it
Any help would be highly appreciated

Its very urgent,
Thanks,