Don't be intimidated by the Epics and Legendaries you spot in Bronze. Some players get legendaries early on but have no proper understanding of gear or team synergy. They're in Bronze for a reason. Read some early game arena guides- most of those will only require your starter champ, a Spirithost, and a Warmaiden, and High Khatun.
For now I'd suggest that you focus on Campaign first, and get your starter to 6*. You'll climb quickly once you get that done- like you said, the epics and legendaries you spot are only on the level 40s. Good luck!
What explanation for this in bronze 4 is this guy u said about y don't u realise the real problem its too hard to play classic matches in bronze tyre if u don't take a proper solution for this problem u lose u r market the game is based on not spending money its gameplay