A compound sentence comprises two or more independent clauses. You may join these clauses by using one of the seven coordinating conjunctions: but, or, yet, for, and, nor, so. Or you may use a correlative conjunction: not … but, not only … but (also), neither … nor, either … or.
You may also join two independent clauses through parataxis, which means pushing the two clauses together without a conjunction. Typically, you'll use a semicolon to join the clauses.
Here are compound sentences formed by a coordinating conjunction and through parataxis:
When you use a correlative conjunction to join two independent clauses, you'll have to use a multiword verb form for the first clause and put the subject between the auxiliary verb and the main verb. Like this: