vector images for coloring pages

You can, but you do not need to modify.

Crediting is more complex. If you credit others, you also need to credit Adobe stock and the creator. It doesn't look to me like editorial use, so I guess that crediting in other cases is optional.

However, if the primary use of your publication are the colouring pages, you will need an extended licence, not a standard licence.

I hope that helps.

Look here for more information on licensing: https://community.adobe.com/t5/stock/links-for-licensing-terms/td-p/11366788

(Disclaimer: As always with licensing, this is my interpretation of the rules. I think they are correct, and the advice is based on reading and interpreting the licence terms and on fair use for both the buyer and the artist/stock company, but I cannot rule out that my interpretation is wrong. I'm not an Adobe employee).