To move around in Lusternia, you will first want to type LOOK or QL in order to see what exits are available from the room you are in. You'll find the exits at the end of the description, and to see what is beyond an exit, you may type GLANCE <direction> or just GL <direction>. To move in that direction, you simply type the direction, as seen below:
There is a limit on how fast you can move, known as celerity. If you move more quickly than you are allowed, you will receive a message saying "Now now, don't be so hasty!" and fail to move. Certain defences can increase your celerity, while other effects can decrease it, effectively making you move faster or slower.
There are also special exits that exist which must be entered. You can use ENTER <exit> and GLANCE THROUGH <exit> to navigate or look through such a special exit respectively.
Sometimes, you will encounter doors. A door may be open, shut, locked open, or locked shut. To try to open a door that lies to the north of you, the syntax would be OPEN DOOR NORTH or OPEN DOOR N. To close a door to the north, you would type CLOSE DOOR NORTH or CLOSE DOOR N. (As you can see, directions can generally be abbreviated in the ways shown above.)
Naturally, before you can open a locked door, you must unlock it, and before you can close a door that has been locked open (imagine a bolt lock that has been locked while the door is open), you must unlock it. To do so, you must obtain a key for the door, which may or may not be possible, depending on the door. There are other ways to bypass doors, but those are for you to discover. To unlock a door to the north, assuming you are holding the proper key for it, you would do UNLOCK DOOR NORTH. The syntax to lock a door to the north is LOCK DOOR NORTH.
There are many ways for insidious players to hinder your movement, and you would be well-advised to learn how to prevent them from doing so.