Washington and Jefferson inherited slaves, it was illegal at the time to free slaves. There were laws in place that prevented people from freeing slaves. There are many facets to the story.
Also, slavery was a normal part of life all over the world, it existed in many forms. It is evil and bad, but it was part of normal life at the time. America didn’t create slavery.
Generals Sherman & Grant (among other northerners) owned slaves. Grant held on to his until after the Civil War when the 13th Amendment became effective. The Emancipation Proclamation only freed slaves in the South. Delaware only ratified the 13th Amendment after 1900. It is inappropriate to judge the past by today’s morality.
It was illegal to free a slave, according to Virginia law. Jefferson tried to get it overturned in the Virginia legislature. Washington had written in his will that his slaves be freed and given generous amounts of land, but that was in Pennsylvania.