Growing personal development brand

Starting personal development brand. Girlfriend has an instagram with 12k followers, pretty successful in real life, and good on camera imo. Just started the YT page.

I plan to spend around $600/month at the start to get this going. Would ideally like to monetize as quickly as possible, but also want legit growth. What would you all do with $600/month to start? How would you monetize quickly? I have been most successful with businesses that produce a quick return (less than 3 months to get rev)

Will link YT channel in messages if anyone is interested in checking it out

Thanks!

what's your GFs Instagram?

Hey John, what is she planning to do (in the long-term) when it comes to monetization?

One to one coaching?
Group coaching?
Selling a course?
Pure ad revenue from YT?

There would definitely be a lot of ways to monetize her brand.
Be it Instagram or Youtube.

Just curious what would that be.
As there are definitely PD coaches making bank with a small following.