Unity how to protect against modification of game files?

Question

Unity

I will have a game on Steam, what is the best way to do it:
In your launcher, check files by md5
Or somehow use the ability of steam to check the hash of the game

Answer 1

Wrote a launcher in C#
Made a check of the parameters at the start of the game if they were not there crashed the game
at startup with the launcher added these parameters
before starting did a check of the hash of files on the PC with those on the server, if there was a difference, downloaded files

Answer 2

disconnect the hard drive. that writes?