Thankfully Microsoft have now added a feature to their Operating System to allow you to burn ISO files without needing any extra software.
To do this, simply
Double Click an ISO file you have on your computer and it should start up the ISO burning software, if it doesn't (because you've assigned ISO files to open with something else) then you may need to
right click the ISO file and then select
Open With >> Windows Disc Image Burner.
You should then see something that looks like the following:
It's minimalistic but it gets the job done if you don't need any special settings or features.