You have just under 7 weeks. I’d start running a few days a week with one long run where you gradually build up your mileages. Could try running intervals depending on how running feels. Intervals can also help prevent injury. It really depends on how you do returning to running. It takes me forever to get back into running shape but I have friends to jump right back in with no issues.

But haven't trained one bit. It's on March 28th. I'm not looking to beat anyone, including my former times given I haven't run in a while. I did the 2017 race and ran an average 10:15 pace, which is my average running pace.

What can I do to successfully train between now and then, meaning finish without getting injured and enjoy myself?

I'm generally "fit" but definitely carrying around an extra 15 lbs. I'm doing a 4x/week weight lifting program that I want to continue (2 days legs, 2 days upper body).