I am struggling to find online players to play with and just to have a muck about!!!
I am playing on Xbox and have used that Looking for Group feature but it seems that when I am online myself (normally 10 pm every night), nobody else is…!!!
Am I missing something or are there just not many people playing this anymore (I’ve only just got into this game - literally a month ago)…?
Have you tried joining clubs that promote group racing? You could also invite others from the loby to your convoy. I don’t know… not good at making friends online. 
Edit: 10pm what zone?
Clubs exist for a reason.
This is that reason.
‘On Xbox One X’ is moot, the game is platform agnostic.
You could also join the official Forza discord - think there are usually some people on there asking if others want to cruise/play/etc.
Use the XBox app on the PC to find groups.