How do I set specific animations to an enemy so that it attacks the player?

Hello, I have just started using Unity and I am making my first game for which I will need a bit of your help. I am making a 2D game in which I created the background, ground, player, player controller. I wanted to go on further to make enemies which will be in different shapes like circle, triangle, etc. Now for the enemy circle I have thought of three types of attacks. One would be the attack to jump in the air and to the player, in another the circle will have inherit blades and will charge on the player and the third one is that the circle will go underground and then come out to attack the player where the player is standing. I know only the basics of Unity and C#. So I just wanted to know that how can I make these 2D animations of the circle enemy and make it attack the player this way. Any help would be appreciated. Thank you!