Yesterday one of the pipes under the kitchen sink came loose. Water was flowing from places it shouldn't be flowing. Turned the water to the sink off. Jammed the pipe a little tighter. Now I need to view some youtubes to see what I need and whether I can fix it (or play the neighborhood Blanche DuBois)
New kitchen...should be plastic PVC. The fittings will either be glued or threaded (most likely and hopefully threaded).
If threaded get a roll of teflon tape, grab some rags and a bucket and eyeball to make sure everything is lining up properly, it's easy to bump stuff loose...loosen the offending joint by turning the threaded nut make sure the pipe hasn't moved down or been bumped off connection if so fit it properly...wipe the threads dry, apply 1 layer of teflon tape...slip the nut back in place...re-tighten.
Search out See Jane Drill on youtube...she has some good videos on all kinds of stuff.