I read that a clean install rebuilds partitions and makes a recovery partition.
My question is does it allow you to pick the size of the partition that Windows 10 is installed to ?
I have a 1 terabyte drive but like to install in a 100gig partition.
I think I will delete the existing partitions before I start
Windows 10 - Clean Install - Windows 10 Forums
I've only used the partitions created by the installer in my own Win 10 systems, but you can certainly manually re-define the primary partition(s) during a clean install. As long as the install partition for Win 10 is large enough (100 GB is more than enough), you'd be fine.
After the clean install it is very easy to resize the partitions created by the install (and delete the recovery partition) and create a data partition with MiniTool Partition Wizard Free.
Best Free Partition Manager for Windows | MiniTool Partition Free
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