Here is what Mueller said in his statement about Hillary;
"Russian military launched a concerted attack on our political system.
The indictment alleges that they used sophisticated cyber-techniques to hack into computers and networks used by the Clinton campaign. They stole private information and then released that information through fake online identities and through the organization WikiLeaks. The releases were designed and timed to interfere with our election and to damage a presidential candidate. And at the same time as the grand jury alleged in a separate indictment, a private Russian entity engaged in a social media operation where Russian citizens posed as Americans in order to influence an election"
The Report it self states; " The campaign evolved from a generalized program designed in 2014 and 2015 to undermine the U.S. electoral system, to a targeted operation that by early 2016 favored candidate Trump and disparaged candidate Clinton. The IRA’s operation also included the purchase of political advertisements on social media in the names of U.S. persons and entities, as well as the staging of political rallies inside the United States. The investigation did not identify evidence that any U.S. persons conspired or coordinated with the IRA. Section II of this report details the Office's investigation of the Russian social media campaign"
That is what he is going to say about Hillary.
As for Comey, this comes in part two of the Mueller Report which states;
January 2017, incoming National Security Advisor Michael Flynn falsely denied to the Vice President, other administration officials, and FBI agents that he had talked to Russian Ambassador Sergey Kislyak about Russia's response to U.S. sanctions on Russia for its election interference.
Then we come to Trump and Comey "the President cleared the Oval Office to have a one-on-one meeting with Comey. Referring to the FBI's investigation of Flynn, the President said, "I hope you can see your way clear to letting this go, to letting Flynn go. He is a good guy. I hope you can let this go."
It goes on to say;
"On May 3, 2017, Comey testified in a congressional hearing, but declined to answer questions about whether the President was personally under investigation. Within days, the President decided to terminate Comey.
As for Obama, the only mention of him in the Mueller Report states;
"On December 29, 2016, then-President Obama imposed sanctions on Russia for having interfered in the election."
All of which you would know if you had ever read the report, so your suggestion that he has some "beans to spill" on Hillary, Obama or Comey only exists in your head.