Hi @cc
Yes, you can insert Javascript code by using an action hook like acf/input/admin_footer. This page should give you more idea about it: https://www.advancedcustomfields.com/resources/adding-custom-javascript-fields/.
If you want to add PHP code, you can use other action hooks like acf/render_field. Please check this page to check the other hooks: https://www.advancedcustomfields.com/resources/#actions.
I hope this helps 🙂
