First step, of course, will be to get the necessary 2/3rds vote in The Commons! I'm not sure whether it was wise for Corbyn to commit to backing the election! Assuming the polls are even somewhere near correct, Labour likely to lose a significant number of seats and he is likely to have to resign, or at least fight (another) leadership battle!
Politicians by default have to say they are always ready to fight an election. To do otherwise would suggest cowardice to the electorate. This will sail through.
TM is not a debater or an orator but let's face it we have had a few of them lately and none have left with people wanting them back. She will concentrate on being steady, avoiding confrontation and by looking like a safe pair of hands. Oh yes, the others are all a bit rubbish as well so that helps.