Still can't make google main search engine - what am i missing?

If that managed line shows up on a personal laptop that no company has ever touched, don't just accept it - that's often an unwanted program that installed a policy to lock the search engine. Type chrome://policy in the address bar to see what's set. Then uninstall anything unfamiliar from your installed programs list and restart; once the program that set it is gone, the setting usually unlocks.

check managed by your organisation in chrome settings. if that line is there, IT set it and you can't change it locally.