Changing colors of the site absolutely is one of the important things and almost all of users looking for colors settings. For changing Primary or Secondary theme colors go to Appearance > Customize > Genera Styles
You will see two first options for changing site primary and secondary colors. Please note, if you change colors then all of your site old selected colors will replace with new color in all Pages, Posts, Options, etc.
For example if your old theme color was #4e71fe and also you used that color in the Posts or Pages, then now you want to change it to #ff5722, then all of your posts, pages, options old colors will update to the new color from #4e71fe to #ff5722