My 2002 Isuzu Rodeo Sport Keeps stalling, downshifting fuel guage doesn't work

What is your question?

My 2002 Isuzu rodeo sport keeps stalling when I slow down or stop. It also down shifts to first as I'm driving it about 55 or 60. The fuel gauge works half the time and the dash board lights keep coming on and off. Sometimes it is hard to start back up whenever it stalls could it be the computer?