The Constraints panel

• Waypoint at N — pins where the character stands at the current frame. Drag the circle to where it should be; the route between waypoints is the model's to plan. Grab it by its rim (it lights up white when the cursor is on it; the inside of the circle is left to the foot bones), in any mode, pose mode included, without leaving it. A click selects that waypoint; Shift-click adds it to the selection or takes it off. Dragging a selected waypoint moves all the selected ones; Esc or the right mouse button cancels the drag. The rim shows only with overlays and Show Gizmo on. Each waypoint is a row: its frame (edit it in place), its Facing (Along path, or Set with an angle), a button to go to it, and one to remove it. Face along the path also tells the model to face the next waypoint at each one; it is off by default, since the model faces the way it walks.
• Pin — holds a hand or foot on an empty, so it stays on an object.

Waypoints and pins belong to the character that was active when you made them. A root-path curve from an older file still works, and To waypoints converts it.