Anyway go play against a real opponent as the AI does some weird things.
Too many things to list.
- Poor build order. You should get a Kubel first and let it cap the other side of the map while the Sturms play aggressive and try to deny the enemy, don't play passive with them
- Build more infantry, you tech up too fast. I was wondering how you had so little resources despite only having 4 units then I realized you bought both trucks. The ISG is mostly used as a reactive unit if you know the enemy is playing passive and you need to unroot them. But most people get the second truck with the Luchs light tank on it and rush that.
- Your micro is poor, the Luchs is really fragile yet you drove it up and past a Bofors, destroying it. you should make sure the Luchs doesn't meet any light tank and if it does, reverse it out asap.
- A build order I recommend is: Kubel, Volks, Volks (Another Volks if you have the manpower or need it), Get a truck and build the 2nd one that can repair, buy a Luchs and harass the enemy. Once they bring out AT either equip your Volks with the Panzerschreck and use them to screen for your Luchs or try to flank them if it's an AT gun or something.