Migrating from Ubuntu

Unfortunately used to Ubuntu since I was introduced to it at my workplace. Now I would like to switch to PureOS. I have about 50GB of data, on the hard disk. Can PureOS be installed in place of Ubuntu keeping all my hard disk data intact ? Are GNU tools preinstalled by this OS ? Also this is slightly off topic but I have my my web-site on www.complimentaryware.info or www.wereco.org . I would like volunteers who are willing to test some s/w I have coded ? I can only provide the source.