About DOS and the Internet
Limits
Although the Internet predates DOS, DOS doesn't have any decent
ability to access the Internet. Even if it did, a lot of the
Internet's content these days is graphical.
When using DOS to access the Internet, the best bet is to use
a terminal emulator and a shell account.
Terminal emulators
Case sensitive
Unix is always case-sensitive. Always.
Get a book on the subject
Buy a book about using UNIX. UNIX Communications and Networking,
by Kevin Reichard and David Burnette, published by MIS: Press, ISBN
1-558828-388-9 is recommended by one user.