Yeah, 0 rpm is dead stop..  1 RPM is precious little better.
Holy sh.t!

Seriously, the numeral one (1) means 1000 rpm on most meters.  Zero is still
pretty much zero
Your description gives no clues about what may be happening.

    Hello there, well I assume you mean when you start it it idles
below 1000 rpm and later it idles (foot off gas pedal) so low it dies.
In these cases I check for air flow problems.  Will it stay running if
you keep your foot on gas pedal pressed alittle? If so try removing
rubber intake and spraying out throttle plate and idle hole visible
near throttle plate with carburetor cleaner and running engine till
cleaned out.  Repeat process a few times till pasages clear and engine
idles good.
    If the car has a MAF sensor (Mass airflow sensor) you can't keep
car running while spraying the carburetor cleaner, but if it has a MAP
sensor (Manifold air pressure sensor) you can usually keep the car
running without the rubber intake hose connected and have someone keep
engine running by pressing on gas pedal (keep it around 2000 rpm, don't
overrev engine) also make sure emergency brake engaged and in park,
automatic, nuetral ,manual, and maybe have person step on brake pedal
while stepping on gas pedal, or chock wheels with a wood block.
    If aflter cleaning idle is still too low they sometimes have a
screw on throttle chamber to adjust minimum air flow on base idle.  Not
the screw that the throttle plate rests on.  If you adjust that screw
will throw off throttle plate sensor setting.