Contrary to other comments, it’s actually pretty common and easy to install Linux alongside Windows, if you have a harddrive big enough for both. If you want to have both installed, it is recommend to start with Windows because Linux boot loader can recognise Windows partition and integrate it with no problem. And Linux natively supports ntfs so you can seamlessly access all your files absolutely no problem. But if it’s your first time installing Linux it’s easy to mess up and kill the windows partition if you aren’t good with terminology yet, so backing up all your files is not just recommended but straight up required.