That is not a bad report. Though I understand that you are disappointed.
It has some very positive comments about extremely important social skills and developments which many children, (but not your boy!) often struggle with. It is also stating, presumably accurately, that your child, who is six months younger than the oldest children in his year, and has had a difficult year health wise ,is not achieving the range of targets that are set nationally for all reception children.
I always think the reception year is particularly hard for any child born later than February /March. When you are only five a six month difference in age is HUGE. It is a tenth of your total life experience. As children get older that difference evens out substantially.
Don't spend the whole summer fretting about it, concentrate on having a happy and healthy summer with your little boy, by all means do a bit of reading, keep practising the phonics, do fun maths . But I would concentrate on developing physical skills, catching , hitting and throwing a ball, riding a bike, scooting, skipping, swimming, climbing in the park, good fun and helping to develop those larger muscle skills which he needs before he develops fine muscle skills. Not "school work" as such, but things that will stand him in good stead in year 1.