lol, no way in hell you can run a straight hour. that **** is hard. try to do something like, run a minute, walk two minutes. adjust it to fit your abilities, but try to stay consistent. the reason for doing that is so that you dont "cheat" yourself by walking way more than you should. if you have a rule, like the one i just outlined, itll keep you from skimping yourself as well as push you to new limits. good luck
oh and also, i would say only run for 30 or 40 minutes at the start. since you lack motivation like you said, its important to set reachable goals. you cant just go from never running to running for an hour every day, it just doesnt work like that unless you had a sudden epiphany (which led to motivation. motivation is an extremely important aspect to fitness). and since youll be running on a treadmill, which is boring as **** imo, make sure its set up in front of a tv, or set up some music or something, itll help you get through the 30/40 minutes.