i always die in world 3 or 4 some tips?

Hi, the game is fun, but I do not know how to safe my progress. every game I have to start from the first world. I know, noob question, but I cannot find help anywhere :/

on the market, pls give a save option to continue later. On a long run, sometimes I want to left the game and continue later. If there is, I could not find it.

Just opened the daily challenge and saw this guy with a score of 90 900, and only got to level 2-1. Player name is PLAYER. seems fishy. Highest score i've ever seen in many months of playing is over 60 000. and that is after finishing the challenge. I took a screenshot....