Docker will have only exposed container ports if you told it to.

If you used -p 8080:80 (cli) or - 8080:80 (docker-compose) then docker will have dutifully NAT’d those ports through your firewall. You can either not do either of those if it’s a port you don’t want exposed or as @moonpiedumplings@programming.dev says below you can ensure it’s only mapped to localhost (or an otherwise non-public) IP.