I don't know how to get to a precise time by numeric entry.
You can manually move the playback thumb, or use the Down Arrow to select the position OSD and then use left and right arrows.
If you want to pause the video and have it automatically begin playback where you left off, enable the Use Bookmarks tag (which is set to Default normally, so it being set depends on the media type / sub-type; the rules are internal to MC, and I don't know exactly what they are).