What happen at the beginning of the civil war?

Answer 1

Nothing much.

Two national armies having to be recruited, equipped and trained from scratch.

A false start when Northern politicians urged a march on Richmond. This battle demonstrated that the armies were nowhere near ready, and it would be another seven months before an effective campaign was launched.

On the Naval side, two important projects started to take shape. The blockading of Southern ports would prove very effective in due course. And the Union decision to build a fleet of gunboats on the Tennessee and Cumberland rivers would also speed-up Grant's Western campaign.