i struggle with skin so take my method as just rough advice!
prime everything that will be skin with white, flat, spray paint. i used to only use walmart .88cent flat white but they quit having it, so now multi surface krylon flat white.
assemble figure.
paint everything no skin first. let all that dry so you know you are happy with it.
start painting with very watered down flesh tone acrylic paint. not washes, but pretty close. let that dry.
if after dry you are not happy go a little darker. if you are happy some washes will help make it look real.
give everything a day to fully dry. if you want shiny then seal with a quality gloss clear spray paint.
i use cheap walmart acrylic paints and mix flesh on the pallet while i paint. white,peach,brown, green usually get in my skin tones unless i'm just painting over factory paint then i just wash with light browns.
sgcaper paints really well and uses black primer. drbindy paints ultra real and uses lots of washes.
it sounds like you want them to look like toys and not real. i think you should find someone who does that style you dig and ask a bunch of questions
i bought an airbrush set after seeing some amazing paint from indrox1 yrs ago. i blew paint water everywhere and parts off my bench. then spent more time cleaning up than building the figure!