Hello @The_Raging_Beard buddy,
Since you have tried so many solutions and none worked, let me try and help you here.
I hope you won't get annoyed with my guide, as it is a lengthy one. (Doing my absolute best to help you here).
I am apologizing to you in advance for such a lengthy guide, as there is no 100% guarantee this would work, but hey it is definitely worth a shot.
Steps to perform on Steam application:
1. Backup F1 24 game (So that you need not redownload 60 GB again)
2. Once game backup is complete, Uninstall the game.
3. Next, open Steam Settings navigate to Downloads and Clear Download Cache. Doing this will re login you into steam.
4. Login to Steam, and just close Steam app.
Steps to perform on Windows:
Assuming you have uninstalled F1 24, please do the following:
1. Delete F1 24 game folder from where it was installed (in case there are any files remaining).
2. Delete EA folder present in C:\Program Files\
3. Delete F1 24 folder present in C:\ProgramData\Codemasters\
Next you need to download some more folders from you "Your_Username" folder located in C:\Users\"Your_Username"\AppData\Roaming\
"Your_Username", would be your profile name, that is logged into Windows.
If the below folders are not visible, please "enable" Hidden items. To do that, click on View - Show - Hidden Items.
Delete the below folders:
1. Delete EA folder present in C:\Users\Your_Username\AppData\Roaming\
2. Delete Electronic Arts folder present in C:\Users\Your_Username\AppData\Roaming\
3. Next, delete the F1 24 folder present in C:\Users\Your_Username\Documents\My Games\
Once that is done, reboot your PC. Next, lets clear the temporary files out of your PC.
Open Run by using keyboard shortcut, Windows Key + R
1. Type temp and click on enter. Delete all files and folders from here. (If you get any warnings for files or folders that can't be deleted, just click on Skip)
2. Type %temp% and click on enter. Again, delete all files and folders from here. (If you get any warnings for files or folders that can't be deleted, just click on Skip)
Next, let's do a disk cleanup. (So that some unimportant and non-necessary files are deleted)
Click on start and type in Disk Cleanup. Make sure you chose C Drive (assuming you have your Windows installed there) and click on OK. (Screenshot Attached)
Check all the boxes that show up, and then click the box that says Cleanup system files.
Again, you will receive a popup, choose C Drive and click on OK.
Wait for the cleanup to complete and reboot your PC again
Next open Steam. Once open, click on Steam - Restore Game Backup... (Screenshot Attached)
Use the Browse button to navigate to the folder location where you placed the backup of F1 24 game.
Once the backup is restored and game installed, please Verify the game files again. If something needs to download or update let it happen.
Once all is done, launch the game.
Again, apologizing in advance if this doesn't work for you or help you.
Wishing you all the best buddy! I really hope this helps you.