To be an SEO expert begins with one key step: You have to execute.
You never become an expert by reading tons of guides.
Although there are lots of awesome guides out there, especially Backlinko by Brian Dean, such information is not going to do you any good if you don't execute them.
The key is implementation.
Now a lot of people are so scared of failing they don't even try, and this is precisely the problem.
Please understand the first few times you try SEO, it's probably not gonna pan out for you, but you have to keep trying and you have to keep learning from your mistakes.
That's how you become an expert.
That's how you scale up over time.