Mirokhodets
When you install Debian with encryption (usually LUKS — Linux Unified Key Setup), only the partition where Debian is installed is encrypted. Windows will remain on a separate partition and will not be touched. Debian encryption does not break Windows, provided that: The partitions for Windows and Debian are clearly separated. You do not change or delete the Windows partition. The bootloader (GRUB) is correctly configured and not damaged. Usually, Debian will install GRUB, which will recognize Windows and add it to the boot menu. If something goes wrong during the bootloader (GRUB) installation, Windows boot may temporarily break. But this can be fixed — you can restore the Windows bootloader using a bootable USB stick. It is always better to back up important data before installation. When installing Debian, choose manual disk partitioning to accurately specify the partitions. Use encryption only for the Linux partition, leaving the Windows partition alone. Save a backup copy of the boot partition (for example, EFI) or make a full backup.
Well, there are sites that will help better than programs and vice versa.
- Google Slides Free and quite convenient. Works in the browser and has mobile apps. However, this is a cloud service, so if you need a completely offline experience, it will not work.
- OnlyOffice Presentation The free part of OnlyOffice includes a presentation editor. Can be used offline in a mobile app or desktop. The interface is more modern and convenient than Impress. Partially FOSS (client is open), you can disable the cloud.
- Calligra Stage Part of Calligra Suite is a free office suite with a presentation editor. There are versions for Linux, Windows, but there are no official mobile clients. The interface may seem unusual, but the functionality is decent.
- WPS Office (free version) Free office with presentation support. The interface is similar to MS Office, convenient and modern. Not fully FOSS, but free and works offline.
- Deckset (for macOS, paid) A very convenient tool for creating presentations based on Markdown. There is no free alternative on Android, but this is an example of the approach.
- Marp Markdown-based presentations. Free, cross-platform (there is an Electron version). It requires a little getting used to Markdown, but it is very flexible and convenient for those who like the text approach.