To move, simply press and hold the right mouse button.
To use a skill (more information on skills below), click on a skill object (Ex: Click on a tree to cut it down or click on water to fish). When your mouse is hovering above a skill object, your cursor will change to something related to that skill to help you out. Ex: If your mouse is hovering over a tree, it will turn into an axe.
The interfaces on the right side of the screen include skills page and an inventory. The skills page is described more below. The inventory holds all of your items including resources such as logs, ore, bars, and fish. There are 18 slots in which items can be held in the inventory.
If you are carrying too many items, you will become overweight and will not be able to move until you are holding less weight than your max. To drop an item from your inventory, click on it and then on the trash can in the lower right-hand corner of the inventory.
Your skills page gives you information about skills if you hover your mouse over the skill name. It will tell you your current level in that skill, the chance of progressing to the next level when using the skill, the number of times you have used the skill since the last time you gained a level, and a brief description of what the skill does. Also, if, for any reason, you want to abort a skill (change back to your normal character and stop using the current skill), just double right-click while using the skill.
First of all, click on a tree to turn into a lumberjack who will move towards the tree and cut it down. After you are done cutting down a tree (it may take a while at a low level) you will have a chance of progressing to the next level, and a log will appear in your inventory. Although it is not a skill, you can burn the logs and create a fire. You can use the fire to cook fish which is explained in greater detail in the cooking section of this help page.
When you click on a rock, you will turn into a miner that will move towards the rock and mine it. When you are finished you will find that you have had a chance to learn something new to help your mining (leveling up), and a shiny new ore in your inventory. Each rock contains several ore. You will notice that for different kinds of rocks you will need a higher mining level and you can only start out mining iron ore.
When you create a fire (click on a log and you can build one next to you), you can use it to cook your fish. Just click on the fire (if you are close enough to it) and select which fish you would like to cook. Note that the better the fish, the higher level you need to cook it and the harder it is to cook it properly. You can also use flour (use wheat on windmill to get flour) to make bread at level 20 cooking. Wine can be made with grapes, also obtained through farming. Go to a bakery to make bread or wine.
Farming was added to the game in an update. The first place you can farm is in Dark Village. You can harvest grapes or wheat. You can turn wheat into flour at a windmill. As mentioned in the cooking section, you can make bread out the flour and wine out of grapes. At a low level of farming, it may take a while to harvest wheat or grapes. The more you progress through your levels, the faster you will harvest. You also have a chance to keep harvesting after getting a harvest. For example, if you are harvesting wheat, you have a chance to get wheat and continue harvesting for more.
Another panel is the Quest List. It tells you which quests you have not yet started (in red), quests you have begun but not finished (in yellow), and quests you have completed (in green). If you click on a quest name, some information about your current task will appear in the chat. Doing quests will increase your knowledge of the game as well as give you some nice rewards.
There are 2 places you can store items. These are your inventory and your bank.
The inventory contains your valuable resources gained from your skills. It also contains other items, such as items obtained through quests and items required to use skills (such as axes, fishing poles, etc). These items can be dropped by clicking on an item and then on the trash can.
Your bank account will be able to hold any items from your inventory. If you wish to place an item from your inventory into your bank or back again, simply click on it. The bank is great for storing items that you don't need at the moment.
You can trade items or resources to other players near you. If you want to trade with someone, click on their name in the chat and then click on "Offer Trade". If they accept, they will click on the same button that would display "Accept Trade" on their screen. This will open up a trade screen on each of your computers, and you can offer items to trade by clicking on them from your inventory.
You can also send items (or messages) using the MAIL system. If you use this method, you do not have to be near the other person, just near a MAIL Port. These are floating rotating green grids found all over Cidade. Simply walk next to one and click on it to recieve/send MAIL.
You can get a visual of what is written here from the login sceen (by watching a tutorial). If you still have a question, try posting a question on the forums.