Rent a bike or buy very cheap second hand

Hey all, ive only ridden my friends bike for maybe 5 minutes and thats all the experimece I have. But now I want to learn and ride a bike for life ! So I just wanted to know if I should rent a bike to practice or buy an extremely cheap bike to practice.

Im scared to scratch the rented bike and pay more in damages but at the same time if I get a second hand bike the issue would be that it would be like 10 years old and im moving out of my country in a month and then it would just be sitting collecting dust.

So need some guidance.

And I also want to ride a cruiser in the future so should I rent a cruiser bike or any bike would do to learn ?