well, humbert, of course the answers to all of those questions will likely turn out to be that flynn was not conspiring with the russians to defeat hillary.
since tapes do exist of flynn talking to the russian ambassador, one would think they would have been leaked to the wa post already if they contained damaging words from flynn. they haven't been leaked, so they likely don't contain anything, IMO.
the rest of your questions about comey, etc. can be answered simply by saying that trump didn't do anything illegal in talking to and then firing comey and in his mind was just trying to get control of the situation.
dershowitz lays out the case why trump's actions with comey were not illegal:
Alan Dershowitz: History, precedent and James Comey's opening statement show that Trump did not obstruct justice
if you are looking for a conspiracy (between the trump campaign and the russians to defeat hillary), humbert,
you will likely see a conspiracy everywhere and are really really hoping that these are the answers to your questions:
Why did he fire Comey?
because comey was onto trump and knew that flynn was trump's contact with the russia intelliegence services who conspired with trump to defeat hillary.
Why did he breech the firewall between the FBI and the White House by asking Comey to stop the Flynn investigation.
because if flynn is exposed for being a traitor to the u.s. who conspired with the russians, then it might come out that trump was in on the conspiracy, too.
Why did he ask Comey for a pledge of loyalty.
because comey had two choices: be fired or become a puppet of trump and don't tell anyone the truth that trump is really a puppet of the russians.
Why did he wait 18 days to fire Flynn when he knew that he lied to Pence.
because trump had to make sure flynn had his story straight and wouldn't expose the conspiracy.
Why did members of his team have so many contacts with Russian agents that they lied about ever having?
after the election, flynn used the meetings with the russian ambasador which were set up to talk about having open lines of communication between the two countries, especially for dealing with syria,
to talk about what trump can do for putin since putin helped trump win the presidency.