Welcome to the forum. Generally it's recommended to feed a food that has proper calcium to phosphorus ratios to encourage slow and steady growth. There's some info about that in this thread. Scroll down a bit.
http://www.mastiff-forum.com/index.php?threads/cane-corso-puppy.31493/
I also posted some info about socializing from Denise Fenzi, who is a positive reinforcement competition trainer, in another thread.
http://www.mastiff-forum.com/index....ing-social-distancing-for-corona-virus.31473/
Stomach tacking. Well, I thing that's a personal choice. Studies are showing that there's a fairly strong genetic component to which dogs torsion and which dogs don't. Of course that's only one aspect to GDV and I think that if you're going to neuter it would be a good time to have his stomach tacked. Neutering is best done for our giants after two years old, or even longer. Those hormones are important for proper growth. Many people choose not to neuter, which I do think is fine if you can be sure that your male won't be able to get to a female. You should also be aware that intact dogs have a high instance of prostate issues later in life. If a testicle is retained, it's imperative to neuter. Retained testicles inevitably end up cancerous. I've dealt with that personally in a rescue.
I hope this helps. Please feel free to ask any other questions you may have and we'll try to help. I'd also really love to see pictures of your boy when you get him.