Congrats - won't take you long to be comfortable. Lot's of apps out there - it will overwhelm you - take some time to learn the ones that come with the Mac - and then when you need something - just do a search on the App Store and you'll probably find it. Welcome to Mac-Forums.
See my essay (link below). Like Brian says, take your time and really enjoy it. The changes might be confusing for a little bit, but you'll get used to it very quickly.
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