Congrates to your new HW!
The answer to Your question is always the same: Only at our official page!
https://lmms.io/download#windows
* install as administrator and grant all users access
A guide for first install can be found here:
https://lmms.io/wiki/index.php?title=In ... on_Windows
The actual 'migration' from your old pc to the new pc, is atm entirely manual, you need to manually copy all files from old pc, to your new, and in the correct folders!
If you are unsure about anything, just ask us