Welcome to the hobby
Once you have wort, there's really no difference between AG and Extract.
There are many guys who started out All Grain from the start, though the vast majority do start with extract.
The thought process is that for a newbie, it's much more important to get the processes like sanitation, boiling, racking, bottling, etc down pat first before throwing on the added complexity of all mashing.
That said, Brew-in-a-bag (BIAB) and batch sparging are relatively easy to learn and perform as long as you can keep the temp and pH of your mash in line.
I've been brewing for about 13 yrs, and I still will make an extract batch every now and then simply to save time. I'd say most of us who've been around homebrew for a while don't consider it backtracking. You can make great beers using extract if you know what you are doing.
Welcome to the hobby. I agree with the post above. You will see plenty of posts disagreeing with me, and the always persistent AG vs. Extract debate. I have been brewing for around 10 years and still prefer to to brew with extracts/partial mash. So I, also, do not consider it a step backward. The great thing about this hobby is that, outside of sanitation, there isn't much you can do wrong. Some mistakes turn out great, and others.....Well almost everyone here has had to dump a batch at some point. The fun comes from constantly learning from each other, and trying to fix/or improve all the time. You'll find yourself addicted to this. I'm still trying to come up with a recipe that my wife will love so she quits buying that damn Summer Shandy. lol
Again welcome and Cheers!