How to make the transition to monetization?

Question

Monetization

There is an educational service. At the moment, about 1K people have subscribed to it. The percentage of subscriber growth is about 15% per month (there is practically no advertising, the service is being tested). There are about 6 months. Active users about 5%.
How do I know if I can start offering paid services?

Answer 1

You can always offer. If they don't need it, they just won't buy it.
The sooner you offer, the sooner you will understand if they need these paid services.

Answer 2

Optional - please suggest.
If you want to force all users, I would wait another year.