Particles not working

I just started learning how to make particles in the niagra system but alot of things that I do dont effect the particles on the screen or even make them dissapear completely.
right now when im trying to change the velocity of the particles using the “Add Velocity” module, nothing changes:

Before that I changed some other things too that made all of the particles completely dissapear that shouldnt, like changing the color and changing the name of a variable, I dont have screenshots of that tho.

You have to add “Solve Forces and Velocity” in your Particle Update to change the position of the particle each tick.
image

thanks