Questions Christians Have About Singleness, Dating, & Planning and Preparing for Marr

Should Christians use online dating services or dating apps? At what point does a woman stop submitting to her father and begin submitting to the man she is going to marry? Should a professing Christian marry someone of a different faith? Since marriage and singleness are both given by God, why are singles often seen as not really into life yet by not being married? How can the Church help foster a better understanding of singleness?