I wouldn't worry about sloppy code. It's like your own messy bedroom - as long as you know where everything is, it doesn't matter how much crap is on the floor. These things only matter when you're inviting someone else inside to get, ahem, intimate.
And using Google and Stack Overflow as a replacement for people around you is not just a solo dev issue. The person on the desk next to you is no more likely to come up with a solution you understand / agree with than someone on the other side of the world, so many people in agencies use both resources equally.
The key thing is to know when you need help and be willing to ask for it, whatever the medium of help that is. I find I solve 50% of my problems as soon as I start explaining them to a colleague, but the ratio is the same when I start tapping out a question on SO.
As for git, get familiar with it using a GUI and then decide if you want to learn it deeply. I use SourceTree / Tower for my solo projects and adhere to Gitflow religiously, but personally the time it would take me to understand the command line method isn't worth the reward I would get out of it.
The root of the sloppy code worry for me is that some day we'll hire another dev and it will take me a month to clean my bedroom!
Of course. The trick there is to make sure the new dev is junior to you and then tell them that's how it's supposed to be done!
I joke, but my experience of coding 'standards' is that there is nothing standard about them, just increasing levels of being anal about how comments are denoted. Code that works and code that is written on budget is more valuable than code that adheres to PSR3 or whatever. It would be nice to hit all three, but the reality for the majority of us is that anything better than 'sloppy' is a luxury we don't have time for.
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