Additional buttons on a homepage

Hello,

I’m using Onepress Plus theme. Everything works fine, but I cannot figure out how to deal with the buttons.

1. I would like to add button to Team and Portfolio sections. Is it possible withou codding? I just want to present section as showing three main contacts or projects and see all button eg

Photo Photo Photo
Link “See all”

If it is not possible without editing core theme, which file should I look for.

2. I would like to change style of the button at Call for Action area. I understand it uses primary button style, which is almost invisible for my main color selection, and I want to use secondary.

Thank you in advance!