WordPress custom post type integration from one theme to another theme

Hi,

I need to switch to a new theme but I want to maintain the galleries created in my current theme, plus creating new ones.

The theme I am currently using is an open source and can be found here: https://github.com/dimsemenov/Touchfolio

I see many php files related to the post type (ds-gallery) and I also understand that I must create a new functions.php in my new child theme folder with the gallery code in it.

Which is your advice for this case? Could a beginner complete this task? Any suggestions?

Thank you in advance