The most reliable method to fix steam_api64 is explained step-by-step below.
Step 1: You need to go to your browser and open up the following link.
Step 2: Then click on the Download option.
Step 3: Once you have downloaded it, click on the downloaded file at the bottom of your browser and click on Show in folder.
Step 4: Now you need to extract the downloaded file.
Step 5: Come up to the extracted folder.
Step 6: Now copy all the files from the folder.
Step 7: Now you have to go to the game folder. In order to do this just go to the
(C:/ drive > Program Files > Rockstar Games > Grand Theft Auto V) and paste the copied Audio folder here.
Step 8: You have to click on Replace the file in the destination option.
Now you are done resolving the issue, and you can run your game.