Good luck with your launch.

Initial and secondary stability are terms for the subjective feel of the boat. Some boats seem tippy but don't tip. That scenario assumes that the primary stability is not great (but can be an advantage for edging turns and chine steering) but the secondary stability often associated with the width at the beam is good. So the kayak tends to wobble, but settle with a lean.

With time and practice a kayaker can become more or less comfortable with a really tippy kayak. The secret is to 'do nothing'. The kayak on its own won't capsize, so with you in it, keeping still, it shouldn't capsize either. The problem is that the paddler tends to over react and eventually flings themselves into the water.

Also the paddlers weight, the paddlers seating (high or low) can also have an influence on stability.

A good low paddle brace works like a little temporary outrigger and can help settle things down. This coupled with wriggling your hips and bracing your thighs to bring the kayak under you [rather than throwing your torso about the place] pretty much keeps you in the kayak and the kayak upright.

The other worst case scenario is the capsize followed soon after by a wet exit bail out. The natural human instinctive reaction when in a upside down kayak is to do the little baby trick of arching your back and trying to get out over the stern of the boat. Arching your back wedges your thighs into the cockpit and you risk shining yourself as you exit. So if you do capsize, bend forward (nose to deck), hands behind you on the back of the coaming and push your butt out of the kayak. Leave the kayak upside down ... otherwise it will fill up with water unnecessarily.

Stick to the shallows and have a spotter with you or paddle with a buddy.

Ideally launch your new boat in a swimming pool under supervision. Do a kayak class and learn to roll.

Be safe

Pete