My 99 Malibu ran hot so I replace the themstat in it now my raditer is making a popping noise I'm puzzled what would cause this

didnt specify much but bad damaged valves --skipped timing chain -clogged cat converter can cause overheated manifold [s ] but are not only reason need to do compression test , timing and exhaust pressure

sounds like you've cooked the engine ,is there any coolant ? is there a spark at plugs ? does the 'whining' sound anything like it might be a metallic sound?

if ran it with ouut water / coolant for to long possible blew up engine --if water going out as fast as putting in --freeze out plug gone or damaged --head cracked --engine block cracked

You need to test the battery to make sure it lost charge. Your problem could be that the engine siezed when it ran hot and what appears to be a low battery may actually be caused by extra force required of the starter to crank the engine.

Timing cover gasket or timing cover cracked this is timming cover


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is electric radiator fan coming on? if not the relay or fuse is bad

sounds like its cranking? check for spark and fuel

check your cv axles in the front end. they are basically your drive axles. the popping while turning is usually the outer boots on the axle shafts have torn and the grease inside the boots has ran out causing the shaft to be dry and click or pop when steering. usually you can replace the boot thats torn but it must be done within a few days of it tearing otherwise you will need to replace the axle shafts.

one or more of the pulley's is defective, most likely the tensioner pulley, but check them all for wear and side to side movement which indicates a worn bearing, this causes the belt to not run true and chirp.

Since you did not mention it, I'll assume the blower is blowing? Preliminary checks to system are: Make sure coolant level is full and has the proper antifreeze mix (heater core can freeze up pretty quick)
If you have a heater control valve make sure it's working. Make sure that there is flow through heater core. one hose going to it should be really hot, the exit hose should be slightly less hot but not cold. Make sure that the plenum door inside the car in the heater box is moving when you change setting from a/c to heat. In checking these things, it's likely you will find the problem or a good clue to it's origin.
good luck