hello guys. new macbook pro user here!

after 16 years of using Windows platform, now i made a jump to give Mac OS a try.
so far, im getting a good experience with this sexy thing. from the very start of booting my macbook, i already amazed with its speed. damn weh 3 seconds to get into login. not gonna happen in Windows platform. haha
Casual usage like web browsing, watching movies, listening to music while doing my work, are quite smooth. Later I will try how this macbook handle development tools and adobe stuff like android studio, localhost, photoshop, AI, etc.
as a new macbook user, there are couple of things that i want to know:
1. is it safe if I installed cracked apps? (appdn.net, cmacapps.com, macbed.com)
2. Do I need any antivirus software installed on my macbook?
3. Is it a must to install utility, optimizer apps like cleanmymac?
4. should i buy applecare? is it worth it?
I have googled those questions. just want to know opinions from you guys too.

thanks.
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