Did all of the soldiers that fought at the Gettysburg fight for the same reason?

The Battle of Gettysburg, which took place between July 1 and July 3, 1863, is considered by historians to be a decisive turning point in the American Civil War. The battle was fought between the Confederate army led by Robert E. Lee and the Union troops led by Maj. Gen. George Meade, in what proved to be the deadliest battle of the war. The soldiers fighting in this battle fought for a variety of reasons but the American Civil War was fought primarily over slavery. The Confederate army was comprised of soldiers from the seven Southern states that seceded from the Union in an attempt to uphold the institution of slavery, while the Union army was made up of soldiers from Northern states that remained loyal to U.S. government and opposed slavery.
While the question of slavery was the primary division that sparked the war, several thousand black soldiers fought in the Confederate Army because they were promised their freedom in exchange (though this shouldn't be overstated as many were simply forced to serve). It is also important to remember that the Confederate Army and the Union army were not entirely volunteer armies. In March 1863, Congress passed the Enrollment Act, which facilitated a draft from the first time. Men were conscripted and faced imprisonment if they did not comply with the law. While the soldiers in this battle may have had reasons for fighting that were motivated by the deeper underlying causes of the war, there is also the stark reality that for many they did not have a choice.
https://www.theroot.com/yes-there-were-black-confederates-here-s-why-1790858546