OK, thanks for that.
That's why the belt has come off or snapped.
The drum should spin freely but something has gone between the drum and outer tub, jamming it solid (most likely).
Alternatively, catastrophic failure of the bearings could cause this.
It's a strip down job (big job) to remove whatever is jamming the drum.
From your earlier post regarding taking the rear half of the cabinet off, I would think that the work may be too much for you.
Basically, you have to take the rear half of the cabinet off.
Then, take the heater out of the tub so you can look inside.
If possible, remove the debris there.
If not, the whole tub assembly has to come out and be taken apart.
If you think you can do the work, try it and get back to me if you get stuck.
If you think it's beyond you, you'll need to get someone in to do the work for you.
Hope this helps