We use the S+ mod which makes our lives much easier when making taming pens.
For large dinos like the spino, I use S+ behemoth gateways/gates. I’ve got 4 stashed away for when I see a big dino (spino’s mainly. Some other dinos may not fit through a regular gateway).
I setup all 4 gateways/w gates in a rough square, but I leave enough space at the corners so that I can escape the trap. I then set one S+ gate to automatically open & close and set the close delay to 5 seconds. Next I ride a dino that is faster than the spino, aggro the spino, have it chase me to the automatically opening door, door opens, I run inside, spino follows me inside, I run out through one of the corner openings, S+ door automatically closes after 5 seconds, congrats, you have a trapped spino. Now you just stand far enough back that the dino can’t reach you, then start tranqing.
You do something similar with smaller dinos like ravager/raptor/megalosaurus.
When you are done taming the dino, you go around and pick up the gates then gateways, in that order, because if you pick up the gateway first, it destroys the gate, and stone behemoth gates can be expensive to build at first.
As for leveling your spino, all combat. Health and melee. How much health vs melee? That depends. If you get a low level spino (75 or lower), it will be unreasonable to try and get it’s health to boss level fighting (10K+). Initially, I would shoot for 5k health. That should give you enough to take down most regular dinos and be able to survive if you get a minor swarm on you.
I’ve found that making a general purpose dino pretty much means you have a dino that isn’t really good at anything. You may have to do this when first starting, but once you can get a good dino, it’s all about specialization. For example, I have 5 crabs. One I’ve designated as my cargo hauler. Once I got his health to a decent level, I’ve done nothing but pump weight. Another crab is just for combat, etc.