Stack three books for your hands and do pushups. Get the rubber bands and put in a door crack and do flyes. Weighted backpack dips. Lie on your back and catch a sandbag and as fast as you can try to throw it threw the clouds, repeat then flip over and crawl like spiderman without going to your knees. The spideys will rip up the upper body. If you can’t get to the gym then use what’s available to you.
Just remember all a bench is, is a flat object to push weight from the chest. You can use or build anything to simulate a bench and any object can be pushed from your chest. Be creative