We're all experts, just ask us. LOL!!
Had the engine ever been fired before or had it been sitting for a while? If so did you prime the engine before starting it?
Yes, you can adjust them, the nut in the center of the rocker should have an allen set screw in the middle, you back that off then turn the nut. The allen screw pushes on the end of the stud to lock the nut in place.
As far as figuring out if you have a solid or hydraulic cam. I believe if you pull out a pushrod, you can look down the hole at the top of the lifter. A hydraulic lifter has a retaining wire clip that looks like a couple of parallel lines near the outside edge of the hole where the pushrod goes in the center. If you don't see these, then I would think you have a solid lifter cam. Whether or not you have a hydraulic or hydraulic roller cam, you might be able to see the connecting bars or spyder if so equiped. The only solid lifter lifter I've ever had was a roller cam amd I don't recall what the pushrod cup on it looked like.