Bowdon there is an option but microsoft bizarrely think its only suitable for enterprise users and that is Windows 10 LTSB.
Apparently tho you can get it legally as a consumer by buying a bulk amount of cheap software from microsoft's website which then qualifies you as a volume license customer, you sign the agreement, and then should be able to get a copy of LTSB windows 10 from a reseller, and activate with your volume license ID.
Otherwise its using Windows 10 pro/education/enterprise and then setting updates to delay feature updates for the maximum time which I think is 180 days, also set to semi annual channel. You will tho still eventually have an build update forced down your throat but it will be delayed by half a year at least.
Windows 10 LTSB is supported for 10 years on security updates, and has no new feature build updates. The license is only valid for that build so is downsides as well, if you want to update to a newer LTSB build it has to be done manually and with a new license.