Aphid. A sucking pest. Many different kinds, and come in various colors.

Squish it and all its relatives. Or wash them off.

And a a new gardener, you need to know that buying ladybugs isn't helpful as they leave! Plus the collection & sale of ladybugs is decreasing their populations.

Better to learn the common beasts & friends in your garden, then learn how to manage them wisely. When you limit pesticide use, the beneficial insects already at your place will thrive and multiply.

Continue to ask questions as gardening is one of those learn-by-doing sort of things.

Enjoy your garden!