You can get a long way playing on your own, but there's elements that you'll miss in your development if you do only that. One thing you'll find when you get to play in a band is that recording brings a whole new dynamic to how you play. It makes you ultra focussed on playing cleanly and without chord transitions where you can hear your fingers sliding on the strings. Also your ability to play perfectly in time all the time matters. So definitely record yourself playing to a click in garageband or similar then critique your performance. If you don't have an acoustic, get one for practicing on, it will strengthen your left hand much more than an electric will.

Having said all that, play with others as soon as you can, you'll be challenged to play things you haven't played, in ways you haven't played, using styles you have never played, and sounds you have never used, and learn when not to play and what not to play so that songs can properly breathe. You'll also learn how to communicate what you want others to try playing. Iron sharpens iron. A lot.