How do I move all of my microsoft files to office libre

Am trying to use office libre and want to delete Microsoft office without losing some files.

The LibreOffice documentation files are here.

I would recommend starting with the Getting Started Guide first. Read it with LibreOffice open, and work through setting up your preferences and trying out the creation and editing of new documents first. Once you familiarize yourself with the basic programs you can open some of your Office files in LibreOffice.

Right click a MS Word file. Select Open With.
Select “choose another app”
Check the box “always use this app”
Select LibreOffice.
Click OK

Do the same for any other MS Office files you have such as spreadsheets.

However, I suggest you not uninstall MS Office unless you need the space. Sometimes, not often, but sometimes the document will look different in, say, Word than it will in LO or OO. Usually this is formatting stuff.

Another, and perhaps quicker, way (in Windows 10) is to change the default application for the file type. That will remove the need to treat each file separately. Go to Settings- Apps-Default Apps-choose default applications by file type. Then look for the MS file types you want to modify, such as .doc/.docx / .xls / .xlsx and so on. Click the current file type indicator (or ‘choose a default’) and select the LibreOffice application you want to use.

With some experience you may decide to actually move to LibO.

Even if your decision not yet is definite, or if you want to apply it only to a sub-tree of your office-files and/or not to all of the document types: There Is
File > Wizards > Document Converter.... It will preserve the original files and you can have original and converted version in the same folder or the converted ones in a different tree by your choice.

The conversion will nicely run unattended.

The Wizard will also offer to create a log. It will be, however Windows style: as-little-useful-information-as-possible-and-inappropriate-presentation. It hides the folder-paths and is created as a text-table in an .odt-file. (How I hate these silly misconceptions! I feel tempted to write a little BASIC macro for the purpose doing it based on a spreadsheet document using a sheet for each convcersion job: definition and log. Well, I would limit the number of files per job to 1048576. Or are these too few?)

Please notice: It’s unlikely that everything will be perfect in the new files. Youshould be prepared to need some fine-tuning in specific cases, and documents well derived from native tempalates in LibreOffice will soon be your preferred choice.
I personally don’t use presentations (Powerpoint / Impress), but I was told that conversion in this case often is not satisfying.