To cover distances in big seas in Atlas you will need a ship, boat or a raft. At the beginning you can start with Raft and Boat. They are not available instantly to unlock build a tiny ship yard.
For this first unlock Seamanship skill by going into Survivalism > Basic > Construction. Click the construction tab under Skills and follow Basic of Building line. Unlock Weaving > Secrets of Building > Go Left for Seamanship. Go to Seamanship Tab and unlock Basic of Building that will give you access to build Tiny Shipyard. Build a raft and follow the guide below to learn how to control Raft or Boat.
How To Control Raft or Boat In Sea
Controls for Raft and Boat works the same way, once you hop in through tiny shipyard check top right part of screen. There will be a small boat icon with white arrow. The white arrow is the wind direction. On a Boat use the left and right row to point the boat in a proper direction with the help of the white arrow. The arrow size change indicate the power of wind, the bigger it is the stronger the wind blows.
For raft you will see a different controls, spin the sails to control its direction. Just walk near the big log in the front center and you will see a circle with Set Sail Rotation text. You can spin it to control the raft movement in the sea. This his how you control the Raft direction.
In the boat while padding the ship icon on the top right will also have a green semi-circle, if you stay in that it means you are max speed, it turns red once try going against the wind that will slow you down. So try staying in the green one to get max speed and reach your desired location fast.