(Idea discontinued)How to make war space ships

I tried to make a actual space ship with no wing and vtol capability’s but there was two many complications so I will make a very large Space plane using the hull of the fail spacecraft

I making a large space cruiser and i have ran in to three problems I have run in to
1.when going up the ship begins to involuntarily turn to the left or right
2.my ship won’t stay level
3.it is very hard to control and begins to do a flip a round 8000 meters

any help appreciate