Go back to the battery, OP...even though it's new and even though you have the voltage you want to see, that doesn't mean you have the amperage to start your car. It could test fine out of the car, but you know, it's not really pushing anything out of the car...no load on it.
Try jump starting your car...if it starts, then drive for 20-30 mins. on highway. Keep the donor car revving a little and keep them hooked up for 5 mins. or so. Also, double check that your starter cable/connections are good (particularly under the + terminal under hood).
Also, do check that bst...check that battery cables are tight...wiggle them and pull up on them...we've had many cases of that issue happening.
If you've been making a lot of short trips and no long ones, that's why the battery could be new but otherwise drained.
Eliminate battery for sure before moving onto other things.
Clutch switch also, as has been mentioned. Do you have a clutch stop? Remove it.
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