So the description says : you and each creature and object within a 10-foot Emanation

so on a grid  i realize its similiar to a circle   What i trying to find out is, is my five feet (o) option 1 in example below and ten feet to each and every direction   Or is my space part of ten feet.. basically for the line thecaster is on is it 25 ‘  or 20’

is it only looking

option 1: xxoxx

option 2  xxxx.     And im simply taking up 1/2 of each center x) 

and does it change if say a large creature does it 

ie

xxooxx

or 

xxxx and the large takes up center two (plus other lines )

would love to see official graph on these  

I have some pictures in the forum. I'll try to find some, but it's your option 1, and the area changes for a large creature. For Emanations, the point of origin is a creature. Since that creature occupies the entire square, the range is calculated from the edge of its tile outwards.

Areas of Effect

An area of effect must be translated onto squares or hexes to determine which potential targets are in the area. If the area has a point of origin, choose an intersection of squares or hexes to be the point of origin, then follow its rules as normal. If an area of effect covers at least half a square or hex, the entire square or hex is affected.

Emanation [Area of Effect]

An Emanation is an area of effect that extends in straight lines from a creature or an object in all directions. The effect that creates an Emanation specifies the distance it extends.

Here's one example using the Spirit Guardians spell:

I posted more examples in other threads if they might be useful for you or future visitors:

• Grid AoE Mechanics 
• Paladin Aura of Protection 
• The behaviour of spell AoEs and Line spells when originating from larger creatures
• Does Conjure Animals (2024) act like Spike Growth or like Spirit Guardians?

EDIT: just to note the drawings don't use the optional rule in the DMG about diagonals on a grid, where range is measured differently.

The graphs and explranation by TarodNet are on point. If it's within 10 feet of you, it's within the area of effect, so 2 squares in every direction or if you prefer a 5 x 5 squares centered on you.

thanks all.