@Jofes Well first of all, winning as Axis is not supposed to be easy. If it was easy, it would not be a fair game.
If you are consistently losing big battles, you need to take a hard look at your battle decision making. Maybe the odds are not as in your favor as you thought. But if you are always getting terrible luck with big stack battles, yes, there is often no recovery there, as the battle can be game deciding.
With Germany, against a good Allied player, you probably have to risk having France taken in order to make the final push to take Russia. You often will not have the resources to hold France and take Russia. Retake France after Russia falls.
With India, there are so many factors. If UK gets lucky with the big SZ37 battle, it can be really hard to take India any time soon, especially if USA harasses Japan effectively. The big SZ37 battle is actually a reason I am getting tired of this game. It’s a very iffy battle that can go either way and can decide the game. But not everyone does this.
With Japan, try not building any early IC at all. While you can build 8 units per turn, use Japan only. This is faster and more efficient. So build up to having 3-4 transports and ferry troops over. If USA leaves you alone, 4 is ideal, possibly 5 if you want to make excursions to Australia, etc. If UK and USA are both hounding you, 3 transports is max, as you will be building ships and planes too. You will not take India if UK and USA both gang up on you, just rely on Germany to win at that point. In a KJF, you are playing defense, protecting your money islands, ferrying minimal troops to take Russian territory slowly and keep India at bay.
Try the Steam version of this game, not sure if you are playing it. Lots of players, and you can get experience quickly. Just play the Allies and watch what good Axis players do against you.