How are football league positions decided if teams are level on points?

When football teams in the elite levels in England, Scotland, Wales and Northern Ireland are level on points in the league table, they are first separated by goal difference.Goal difference is calculated by subtracting the total number of goals a team has conceded during the season from the number they have scored. So a team who has scored 60 and conceded 55 will have a goal difference of +5.But sometimes, two teams will have both the same number of points and the same goal difference. In that s