Both the House and Senate investigations of the Trump campaign and Russian involvement in the election must continue. The special counsel will not release a report publicly, but will give it to the Justice Department explaining the decision to bring charges or drop the matter. The attorney general would have to notify Congress of the conclusion, but can decide whether to make the special counsel’s report public.
The House and Senate investigations, on the other hand, are public and will, hopefully, inform the American people of everything that transpired, including unethical behavior and identify what enabled the Russians to affect our election and how much effect they actually had. The special counsel will only consider whether crimes were committed.