Partitions for windows dual boot

[yancek]

So can I just partition the ext4 disc with gparted and then install windows. Ideally windows will install on the open part of the partition.

Yes. Use GParted on the 'live' USB of Ubuntu to shrink the ext4 partition(s) to create unallocated space. When you boot the windows installer, immediately after the licensing agreement page for windows, you will see install options and select the Custom option which allows you to select a specific partition or unallocated space.

[MAFoElffen]

So can I just partition the ext4 disc with gparted and then install windows. Ideally windows will install on the open part of the partition.

Sort of. Let me reword what you said so things are clearer. And remind you what others have told you...

1.) Boot off of an Ubuntu LiveUSB to use GParted off of it. Why? Because you cannot shrink a root partition while it is booted off of it, because it needs to be unmounted during the shrink process... You can resize/shrink the partition(s) of the drive, when you are booted from the LiveUSB. That drive will be unmounted.

2.) You do not need to add a partition for Windows to install to. You 'can' (look at the references links below) but you do not need to... You can leave the unallocated space just as is. The Windows Installer media will see the unallocated space on the drive, and suggest that you can install Windows to that unallocated space.

3.) If you do add a new partition, then you would need to know how Windows see's that, and know if you needs to allow space for it's reserved system partitions... to point the Windows Installer to, to install to it. (Also refer to the reference links below) Easier to leave it unallocated, and let the Windows installer figure out what it needs to partition in the unallocated space (for it's reserved system partitions and such).

4.) It already has an EFI partition, which it will share with Ubuntu...

RE:
https://learn.microsoft.com/en-us/wi...iew=windows-11
https://pureinfotech.com/install-win...tom-partition/

Note: Be aware that Windows needs some of those other partitions to be able to recover from, after a Windows update causes a system crash, to prompt you to do a Windows boot repair or system rollback...

Does that make more sense now?