Generally, having a dream about the sea has many different interpretations. Sometimes it indicates a hope for a better future while other time signifies that one is at peace with their current situation.
If during the dream from the shore you saw a sea that was peaceful and serene with only gentle waves it means that you are at ease with your current situation. It is also a sign of the upcoming few months being likewise peaceful and relaxing for you.
A dream in which you saw a stormy sea with thunderous waves from the shore can be interpreted of you needing to be more careful in the upcoming period. Someone is waiting for you to make the slightest mistake and they will without hesitation use your mistake against you in your professional life.
If in the dream you were traveling in a boat and you saw a calm sea it indicates that the next few months will be full of activity in your personal life. Meeting many new acquaintances is likely as is meeting a person which will be interesting for you from a romantic prospective.
If during the dream you travelling in a boat over stormy sea it indicates that you will pull through a difficult situation within the next few months. This is especially true if the boat seemed unaffected to a great degree by the rough state of sea. If the boat was however rocking heavily it indicates that you will have more stress and that things will not be as easy.
The meaning of a dream in which you swim in a calm sea is very positive. Often it signifies that you have achieved a great spiritual fulfillment and that you have no major worries on your mind.
To see a friend/relative swimming in a calm sea it indicates that things will be great for them within the next few months.