It's true. There was one media watchdog group that said that, in 2015, Trump receive 55% of ALL media coverage when compared with the balance of the candidates on both sides of the aisle. That's more than half the coverage balanced against more than 20 other candidates. The MSM loved Trump, saved him a fortune in campaign expenditures to get his message out, and were the first people he turned on when they started to expose him.
That "free press coverage" you talking about was mostly negative. It was designed to do him more harm than good. What would have helped is "honest" press coverage...and he didn't get that at all.
No. That "free press coverage" was Trump's image in the camera, and Trump's words in the microphone. Trump was able to get his message out like literally no other candidate - in fact many times some candidates - and all the while managing to spend virtually nothing of his own campaign war chest on TV spots when compared to his competitors. There is no more "honest" press coverage than broadcasting his every word, every day, at every campaign stop. The free press coverage is the only reason everyone knew "his positions, his goals and his actions".