You have a fill valve like this?
I'd shut the water off, remove the supply line from the bottom of the toilet, if you have a flex point it into a bucket, a hard line put a tray under there and hold your hand around the top of it. Then turn the valve on a second to see if you have pressure.
If you have pressure change the fill valve (fluidmaster). This is the most likely culprit.
If you have no pressure remove the line from the speedy valve and repeat. If this gets you pressure change the supply line to the toilet.