Lights flickering while driving and other problems

So I have a 325ci e46 w 125k. My lights are flickering while driving kinda looks like it blinks(turn off a little/ look like lights are low powered or sum) and turns back on. I also have another issue. My right passenger side, has started to hear a hissing or air. I can’t tell what it is. My tire pressure are okay and are where it should. My car also feels sluggish like half way on the Gas pedal n it’s like 1500rpms and takes a while to switch gears. I’m thinking it’s the fuel pump & sender...

Lights flickering while driving and other problems