Will this plane save me a ton?

My dad has his PPL and owns a Piper tomahawk. Or as I’m reading up lately a “traumahawk”.

He’s always wanted me to get into flight training and I’m just now coming around to it. I’ll be paying my way through training but he says I can use his plane free of charge. I have to pay for the fuel and other stuff of course.

I’m just wondering how much would it save me by using his plane? My goal is to become an airline pilot and get to applying for regionals eventually.

How much would flight training cost on average since I’m able to use his plane? Or is the piper tomahawk not great like people say and I should instead train in a Cessna?

Would love any advice as I’m new to all of this