Essentially [Carrier-Grade Network Address Translations] allow the ISP to assign a single IPv4 address to multiple customers.

[A CGNAT] creates challenges trying to remotely access resources on my home network externally

You can usually tell if you're behind a CGNAT if your IP address is in a private IPv4 address range. [] ... Another method is running traceroute with your public facing IP address. [...] If there's more than one hop, then you're likely behind a CGNAT.

If you're unfortunate enough to be behind a CGNAT, you can sometimes request a static IP from your ISP (usually at a cost). However, there are options to access resources on your home network, such as using a Cloudflare Tunnel.