I would never suggest a new brewer start with all grain. The more moving parts you have, the more variables, the more that can go wrong. And when something doesn't turn out right, how do you isolate the problem?
On top of that, you need to understand how water influences the mash.
No sir--start with extract, learn the boil forward, then think about all grain.
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I taught a newbie how to brew all-grain--but I made virtually every decision for him at the outset. He didn't have to worry about his crush, the gap on his mill, the temp of the mash, how to get that temp right with the thermal mass of the grain and mash tun fighting against temperature, how much water, what water amendments he should have made, none of that kind of thing--to say nothing about being concerned with pH.
He "helped" me do a brew of a recipe he wanted to try, but in truth, I was the one who brewed it. Then we had a second brew day, this time on his equipment, I'd approved the crush of the grain, told him the water he should use and how to dose it with salts, and kibbitzed while he did the whole thing.
Then the third time he did it in my absence, though I had several texts and one phone call during it to resolve issues he'd had. But again, I'd set up the water for him.
This is the only way I can think of for a newbie to start off with all-grain, and have a reasonable expectation of success.
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My suggestion to new brewers: Do 2 or 3 extract batches. Learn how to manage the boil, hop additions, chilling, racking to fermenter, oxygenating the wort (shake it), pitching the yeast, trying to control ferm temp.
Then bottling. After getting a handle on the boil forward, then go backwards to the mash and learn how to do that.