First car what should i do?

I would really love to restore a 67 impala or 96 ford pickup. But my mom has my grandparents 96 trailblazer. The only problem is the transmission needs to be replaced. I think i should pay for the transmission and anything else thats wrong with it so i can save up for my dream car. Should i do that or just buy myself a car?

If the trailblazer is basically free, and you can fix it yourself cheaply, then I would go that way to start with. It gives you a reliable vehicle in a short period of time. You know the history and condition of the vehicle, so you know it's not a lemon, just needs a transmission.

Then you can save some $$, buy the car you want, and work on it in your own time. It might take months and some serious $$ to do a proper rebuild of an old vehicle. If you have a reliable daily driver you aren't under that pressure to get the project car on the road, so you don't take short cuts on the rebuild.

Then you can always sell the Trailblazer later, now it's a decent working vehicle, and get back the money you spent on the parts.