Blog Themes Wordpress Damask Can I Install A Different Wordpress Theme To A Wordpress Hosted Blog?

Can I install a different Wordpress theme to a Wordpress hosted blog? - blog themes wordpress damask

I do not want to start a free Wordpress blog site (my own domain name), but I do not know how the subjects they offer. Can I make a downloaded theme there? I've seen hosted Wordpress blogs with different themes, so I think that's possible.