You may or may not get a score, as schools seem to do things differently, but you can work it out yourself if the school don't provide it.
Each ELG must receive a minimum of 1 point (for emerging), so the lowest score possible is 17 for a child emerging in all ELGs.
Then 2 points are awarded for each ELG at expected and 3 points for each ELG at exceeding. So the maximum score, for a child exceeding all 17 ELGs, is 51.
The pilot showed that the average score was 32 (I think) but only 41% of the children achieved a "good level of development" (GLD), which is gained by a child achieving (so either expected or exceeding):
the early learning goals in the prime areas of learning (personal, social and emotional development; physical development; and communication and language) and;
the early learning goals in the specific areas of mathematics and literacy.
I think the GLD represents 11 of the 17 ELGs, so theoretically a child could achieve the GLD and have a total score of 28 if they were emerging in the 6 other ELGs.
See the pilot report here www.gov.uk/government/uploads/system/uploads/attachment_data/file/190639/DFE-RR291.pdf