Surfing through a proxy server on command line net tool (curl, wget, ftp, gopher and others) or text based Web browser (w3m, links, lynx ect.) in Unix-like OS is possible by setting some environment variables or specific parameters of program in question. Some browsers also support the "no_proxy" environment variable that specifies a set of domains for which the proxy should not be consulted. As for ssh see connect-proxy debian package and ssh man page.
For the HTTP connections assign the ip/hostname http proxy (with an optional username and password) to the http_proxy variable:
$ export http_proxy=[USERNAME[:PASSWORD]@]PROXY_ADDRESS:PORT
For the FTP connections assign the ip/hostname ftp proxy (with an optional username and password) to the ftp_proxy variable:
$ export ftp_proxy=[USERNAME[:PASSWORD]@]PROXY_ADDRESS:PORT