Can I add things made in Adobe Illustrator to Unity2d without buying anything?

I need to make a game for school and I have some things make in Illustrator, but I don’t know how to add them without buying anything.

I’ve never used Illustrator, but I found this tutorial on how to export as a PSD: How to Export Adobe Illustrator CS6 Layers to Photoshop - YouTube

After you export the PSD, just drag it into your Unity project like any other image.

In Illustrator once you have completed your image you simply need to go to File > Export and you can select many options but mainly you’ll select wither Photoshop(*.PSD) or PNG(*PNG) and then from there once they are exported you can use either in Unity without purchasing anything.