Transpose vertical rows into one horizontal cell

Hello,

I'm having trouble trying to transpose vertical rows which once text is populated, and have it appear in a horizontal fashion in a designated cell. I can manually make this happen, but wish to input a formula that manipulate the data like this each time a new row is added. I'm wondering if in this case, it would be best to first indent the bundle step rows as child rows underneath the parent row bundle cat ID.

Thank you in advance for anyone that is able to support.

Video of what I am trying to accomplish is here for reference.

https://drive.google.com/file/d/1fG2GIGl_w7-Sh-4x8WvV1ynBPGv1yR7f/view