I always try to use several layers of protection. First, I encrypt files before sending them, so that even if someone intercepts the data, it will be impossible to read them without the key. To do this, I use programs that allow me to create encrypted archives. Secondly, when transferring large amounts of data, I prefer to use file-sharing programs that support security at the data transfer level. For example,
https://keep2share.tv/categories/filesharing/ is a great tool for large file transfers that secures data via HTTPS and offers features for setting passwords on files. This greatly reduces the risk of unauthorized access.