how do I start?

can I ask a few things?

what are sprites?
are they like empty variables you then put a command for them to move?
are they the design (the pixelated mario model for example)
or am i getting this wrong on a whole another level?

when I tried to make a game, I'm getting a few errors on frame rates
it seems that the commands are not in sync with the visual output
am i getting something wrong

btw I use java

also, there's alot more questions but I'm hell bent on these 2