There are 360 degree longitudes. 80 degree in the east of prime Meridian and 180 degree in the west prime Meridian up to international date line.
You are demonstrating by your question that you do not understand Latitude and Longitude. That you also don’t understand the concept of degrees of an arc or how many degrees in a circle.
So lets start with what Longitude and latitude is. Lat and Long is a grid system that can be used on any sphere or globe Planet Star Moon etc.; to map out or locate any spot on it’s surface. The longitudinal lines are all great circles. They all come together at the poles and run True North and South. They are not parallel to each other and hence the spaces between them are not consistent as they come closer and closer together as they get into the higher Latitudes. Until eventually all meeting at a singular point the North or South pole.
The Latitudinal lines are parallels Only the Equator forms a Great Circle. It divides the world into the Northern and Southern Hemisphere. All lines of latitude are parallel to the Equator and hence to each other The equator is shown as 0 deg North or South. Latitude lines always run due East and due West . Using the center of our planet as the apex. The latitude is a measure of arc between the equator at 0 deg and wherever you project out to the surface. 90 degrees North being the North Pole. 90 degrees South being the South Pole.
Now you should know that there are 360 degrees in a circle. We divide the world into The eastern and western hemispheres. The Prime Meridian or PM is the longitude that passes through Greenwich observatory in Greenwich England it is 0 degrees all degrees are measured East and West of the Prime Meridian. They meet at 180 degrees East and West which is the same line. So just as you learned in your grade seven geometry there are 360 degrees in a circle , THERE ARE 360 DEGREES OF LONGITUDE THAT COVER A WORLD MAP OR GLOBE, or any map of the planet or of any planet. It is the nature of a circle.
However each degree of Longitude or latitude is composed of 60 minutes, and each minute is composed of 60 seconds, and each second can be broken into decimal point allowing ever more precise definition.
On the Equinoxes the Sun will be directly over the Equator. On the Solstices it will be over either of the tropics Cancer or Capricorn. Latitude is determined by measuring the height of the Sun in the Sky at it’s zenith then applying a factor based on the day of the year. Longitude is determined by noting the time that the Sun reached it’s zenith and comparing that to noon in Greenwich Mean Time or GMT ( now called Coordinated Universal time. Each hour difference will amount to 15 degrees of longitude.