Double check burrows and stockpiles set to 'g'ive.
If a stockpile is set to give to any workshop, that workshop can no longer take items that are not form one of thee stockpiles set to 'g'ive to it.
Similarily, if a stockpile is set to give to workshop A, but not to workshop B, the workshop B won't be able to take items from that stockpile.
As for burrows, I am not experienced enough with them, but I read multiple times about them causing a workshop entry to remain red when you have the materials.
If you stockpile your coins, NEVER use bins, it tends to only mess things up, with the job cancel thing when your bins are transported.
Blocks not found, there is usually only one reason, being that you are trying to build in a place that doesn't have ground access to your blocks at the time you are trying.
It can be a bridge retracted, a wrong z-level (easier to make the mistak with the multi zlevel view), stairs/bridge/floor not yet built...
And finally, for farms, humans don't start with underground plants, being an above ground race and all.
My tip for you is to farm above ground, and the easy way to do so is to channel a soil area, to get rid of all the normal above ground things that prevent farms.