A Censure is a formal condemnation of the actions of an individual person. Both the House of Representatives and the Senate can make such a statement. They decide on doing so with a vote, just like with any other decision.
There are no direct consequences when the US President in censured by Congress. It is merely a symbolic gesture.
There were only three cases where US presidents were successfully censured, all of them over 150 years ago:
- Andrew Jackson in 1834 for withholding documents relating to his actions in defunding the Bank of the United States.
- John Tyler in 1842 for various reasons. Long story short: There was a motion to impeach him. When that impeachment failed, a Senate committee decided to at least censure him.
- James Polk in 1848 for inciting the Mexican–American war without Congress approval.
There were also some failed attempts at censuring the president which did not achieve the necessary majority:
- Abraham Lincoln in 1864 for violating the rule that members of congress must not hold an army commission.
- Bill Clinton in 1998 for the Lewinski scandal (the only example from recent history).
The thing about committee chairmanship is specific to the censure of a Congressmember by the Congress. In that case they automatically lose the chairmanship in any Congress committees they lead. But that's not relevant in the case of a censure of the President. The President is not a member of Congress and thus isn't even a member of any committees, let alone chairman. If you have questions about Congress committees, that would be a topic for a different question