Is it better to study for familiarity or in-depth? Is it better to lstudy with or without a partner?

You need to study both, depending on your abilities. Consult with Rabbi Sosonkin, who can introduce you to others like you. A study partner (chavrusa) is one of the ways to acquire Torah, but do not waste time on learning until you have a chavrusa. https://www.torahrecordings.com/rebbe/igroskodesh/011/009/3563