Seals are amazing animals - Should I use a period or an exclamation mark?

It depends on how you want it to sound.

if you said

Seals are amazing animals.

It sounds like a plain statement

if you said

Seals are amazing animals!

It sounds more exciting.

Periods go at the end of declarative sentences, and exclamation points go at the end of exclamatory sentences. An exclamatory sentence is one that expresses a strong or forceful emotion, such as anger, surprise, or joy

i believe that dan is so anxious because he dose not know what awaits him when he gets there. but i dont know to be honest

it states the claim