I understand that you have to slide in order to go through the window but can anyone help me and explain how you are supposed to get upwards and off of the fence, i cant seem to get it and watching people do it isn't helping. If you can help i would really appreciate it.

you kinda just have to spam jump and hope you get up. Its not very consistent. It really doesn't save much time either only ~0.2s I would honestly just recommend getting faster at going the normal way around the house before you worry about getting over the fence.

Alright, i did notice that it only saves like a fraction of a second but i honestly thought it was a lot more significant. Thanks for letting me know!

Btw its not entirely spamming, if you time the jump from the stairs into the kitchen, and crouch before you reach the window. You can jump from the window sill up to the fence.