just want to find out can the company u work for choose when u can have holidays as we r not allowed to take them at xmas and summer holidays times like that is this legal or can u take holidays when u want as u earnt them hope this makes sense 
To answer your question, in short, Yes.
Many sectors of many industries have ‘peak’ times when they will not allow, or limit, people taking their Holiday entitlement.
However, what has not been tested (to my knowledge), is whether these restrictions can be circumvented with regard to requesting ‘family friendly’ hours.
You say you cannot take holidays in the Summer. If you have school age children then your are automatically restricted as to when you are able to enjoy a ‘family’ holiday.
Whilst employers are not obligated to comply with such requests, there is a requirement upon them to ‘consider’ requests for ‘family friendly’ hours, and I can see a valid arguement that ‘hours’ could also include holidays.
Of course, you would first need to establish that the school in question is unwilling to permit short holidays within term time, which many now do within acceptable parameters.
thank you 