Finder tools extend or replace the Mac's file browser. Some add actions to the right-click menu, such as creating new files or opening a folder in Terminal, while others are full alternative file managers with dual panes, tabs and batch renaming. Default Folder X improves Open and Save dialogs.
Path Finder, ForkLift and QSpace are paid Finder alternatives with dual-pane layouts, and ForkLift also connects to remote servers. RClick and SaneClick are open source extensions that add custom actions to the Finder context menu. Finder extensions must be enabled in System Settings before they appear, and some features depend on your macOS version.