Q.I Have A Tree In My Garden That I Don’t Know
I would like to know what it is as it needs cutting back (its very close to our house)

Certified GKH Gardening Expert
It's not really possible to give you an accurate answer based on your photo, but I'm sure a local gardening center can help you with identifying this tree. A rule of thumb about pruning trees is to only cut back to one-third the size of the tree. Any more at one time could kill or debilitate the tree. Here's an article that will may help:
https://www.gardeningknowhow.com/ornamental/trees/ash/pruning-ash-trees.htm