A brand is not a logo. It is what people expect from you before they deal with you — built from every interaction they have had, or heard about, over time. The logo is a label attached to that expectation.
Brand is the accumulated result of things that mostly are not design decisions:
A business with a beautiful identity and unreliable delivery has a bad brand. The design was never the load-bearing part.
Someone might encounter you on a search result, then a social profile, then a website, then an email. If those feel like four different organisations, each encounter starts from zero instead of building on the last.
What needs to stay consistent is narrower than people assume:
Voice is how you sound. It is the most useful brand decision for marketing purposes, because it applies to every word you publish and it is free to define.
A practical way to pin it down is by choosing between pairs: formal or conversational, serious or light, direct or gentle, expert or peer. Write down three or four choices, and one line of what you avoid — for example, "we do not use jargon without explaining it" or "we do not exaggerate what a course will do for someone".
The test of a defined voice is whether someone else could write in it. If your description is vague enough that two people would produce completely different text from it, it is not defined yet — and it will not survive anyone else writing on your behalf.
Practical, unglamorous things that matter more than they sound:
New businesses commonly spend heavily on identity design before knowing what they are selling, to whom, or how they will describe it. Brand emerges from doing the work and finding out what people respond to.
A clear name, a simple consistent visual treatment, and a voice you can actually sustain are enough to start. Refinement is much easier once you have real customers to learn from.