Sorry for delayed reply. Also I was not aware that the links had been blocked by Steam. It was some time ago I created this scenario.
The link to the Virgin Trains East Coast reskin by Albie Pearce can be found at https://superalbs.weebly.com/train-sim-reskins.html .
Unfortunately the UK Train Sim website no longer exists, and I am not aware if the same files for the Network Rail HST Reskin have been made available elsewhere.
If steam blocks the above website address I would try copying and pasting it.

Both of the links are blocked by steam

All I can advise is to make sure you have all the relevant additional items as listed above and that you have followed the install instructions that come with them. If the files have not been installed in the correct location on your computer then this scenario won't work.

hello,i downloaded your Network Rail HST and I've reset my train sim but the train doesn't show up can you help?(I'm new to TSC)

Ok merci pour ce scenario