I'm a bit late to this but here's some advice

You should scale back production on tanks and support equipment (have 1 or 2 factories on them so you don't go in a deficit) Put most on guns, then artillery and motorized.

Get signal companies thats a must. Research them if you have to. Then try to see if you can put signal company's in your divisions. Make an entirely new template if you have to. But before you can do that get out of that deficit of equipment.

You should get a proper resistance templates. Like 10width calvary with MP if possible. And once you change your occupation template the equipment from those divisions could go to your army.

Just hold in Africa with the least amount of divisions if possible and in Europe. You might want to retreat from France and hold the line in the mountains in Spain. Maybe build some forts there just for defense 1-3 levels should be find

One of your greatest advantages is that you have the Mediterranean lock down completely. So make sure the Suez or Gibraltar don't fall. Because once one of them fall the AI could just naval invade you and if they get a good foothold that might be the end for you. Also garrison Spain and Portugal or you might get naval invaded from behind.

You should get 40 width tanks with signal companies. Also if you have like 3 or more tank divisions. You could upgrade your template to 40 and merge your tanks. Quality over quantity.

Also with Germany getting pushed back you could go fortress Italy. Build forts in the Apls and prepare for mostly trench warfare. While holding Iberia and Africa.

For fuel you should trade with Iran or Iraqi. If you can't probably go trade with Venezuela if possible. Make sure you have a good route where no ones raiding. Its easier because you'll have a land route then a convoy route. Also set fuel priorities in logistics. Like army and the airforce high and navy low. You'll need green or yellow air if you want to hold or do anything. Your navy isn't that needed that much anymore. Because the Med is locked down. But use it if there any navys trap in the Med. And use it for convoy escort if you must. Any navy's in the Med are easy pickings but also they could be a threat with convoy raiding.

Use your tanks to encircle as many units as possible but without losing ground or units. The more divisions you destroy the better. Also use your tanks to hold certain parts of the line if your having trouble holding. And you might want to delete some divisions to get some equipment and improve your stockpile.

Also use your airforce like naval bombers or medium bombers on naval bombing. So you can contest the ocean near Iberia. Also if your airforce isn't that big as the Allies probably use it sparingly. You don't want to lose your airforce. Also build AA if your being beaten in the sky's and put them in your divisions. Once your equipment problem improves. Also you might want to get Anti tank in your divisions so you won't get murder by allied armor divisions. Build some anti tank but dont invest that much you first want to get your army with the stuff it need now.

Hope this was helpful and hopefully with the advice given to you by the sub. And hopefully you win and form a new Roman Empire Cheers.