5.6 -> 7.0 upgrade question

Hi people!

I am an experienced (jack of all trades) web master, but fairly shallow knowledge.

One of my sites is using 5.6 and I need to bring it into 7 as modules (WP) are dropping support for 5.

I tried to find an easy resource for 5->Upgrades. Ideally an auto code checker but failed so far. Reading into help articles, I get dumped straight into different functions, this is not helpful as my PHP knowledge is sketchy, I can “code” with examples, but not off the top of my head.

1. Is there a semi automated code checker?

2. AFAIK, my old code uses MySql_ functions which I am sure are killing the code when I flick the switch to 7. Would I be right in thinking thats the main thing I need to fix?

Can anyone who tread this path share their experience?