Just skimmed prev posts so sorry if I'm repeating anything...

Pie hated tummy time until she could roll over. We did it every time she was on the floor, but I had to laugh - the one time I saw the MCHN she said one minute for each week of age (or something like that) and at 8 weeks, there was no. freaking. way she was going to spend 8 minutes on her tummy!

My opinion - it's about giving them an opportunity to move in different ways & develop strength. But at their own pace (every baby is different). So we did do it, but sometimes it would only be 5 seconds or so, sometimes as much as a minute. Once she could roll it was a different story, she started doing 5 minute stints and we were away.

She'll get there

ETA - one thing she did like better, was lying on us on her tummy. So if you lay on teh bed, or lean back in a longe chair, and lay her on her tummy on you, she will left her head to see your face & engage with you, and that is doing exactly the same thing... only she gets to look at your face, which is more interesting than the floor.
Worked for us