It would be a scam if you had to invest your own money. You don’t need to invest anything.
If you post useful content you could get sats, if you choose to. Later, you can choose to redistribute the sats you got by zapping other posts. I never invested a single dollar on Nostr.
Using sats or understanding Bitcoin is not a requirement to use Nostr. In fact, there’s probably too many Bitcoiners here! 😅 But most would be more than happy to answer any questions you may have about it.
Heck, many people even went sats to newbies, no strings attached. A reverse scam? 🤣