Newbie with a common problem

Hi everyone!! New around here!!
I've got a couple a questions to ask.First I gotta say I don't know much about mechanics and more English is my second language...pretty hard to understand you guys sometimes.

First problem like many of you I've experienced idle problem. When I stop to a light after a minute or so the rpm goes weird: under 1000 but the car seems to cough. The only way I found to stop that is to press the gas pedal until rpm reaches 1500 then it's ok. But when the car does that the needle of the gas gauge goes straight up to the full up line??? And behind the car, the air coming out the exhaust pipe sounds a bit like a pop??

Second problem: what's the throttle body kit and how can I see it (under te car??)

Third one: the temp/gauge light is burn. how can I change it?

Thanks for your answers

By the way: 93 escort LX, 1,9L , new alternator, new radiator, new exhaust line/pipe
Xaw57

In a nutshell, you should get a manual such as Hayners or Chiltons, it will help you a lot.
The throttle body is in the air intake pipe, just before it goes into the intake maniflold, car sounds like the timing is out, try getting a tune up done.