Based on the flag{ it looks part of a CTF. Removing the "-":
4e6f5fetc. is hex encoded:No_Aguantaste_El_Tirónu0041u0063u00e1as UTF-16BE isAcá_Te_Doblamos_En_CortoLQFbase32 decoded isYaTeCayoLaBandaDeUHF202020would be a bunch of spaces.
I used cyberchef. The magic function figured out the base32 one, but the rest are recognizable.
I don't think so in your case. From their docs these features are only available for self hosted instances, so you'd have to host Traefik instead of Nginx and end up with a similar config as your current one.
Netbird/Tailscale are at their heart private LAN that you control that routes over the internet. They have some features on top to make DNS/TLS/Services/Tunneling easier. OP is using a service to allow external access to a host on their LAN.
If you wanted to hide your home IP you could either use something like Defelct or Cloudflare as a reverse proxy, or host your own reverse proxy on a cloud provider (either Nginx like you currently are, or Netbird's reverse proxy UI) and proxy it back to your local server over something like Netbird/Tailscale.
DDOS/Scraping protection would depend on the method you choose.