You can edit dotfiles (like .htaccess for example) via cPanel File manager. If you have any problem to view these files in your file manager,
please check enable this options when you first click on File Manager in cPanel a Directory Selection pop-up appears. You can select what directory to open and near the bottom of that pop-up there is an option to show hidden files.
If you still having trouble enabling hidden files, try clicking on the small link in the cPanel footer that says, "reset all interface settings".