You install One2Tree on your web browser from Chrome Web Store. Note that for Chrome and Edge you need to "pin" the extension in order to see it in the toolbar. You can do that in the upper right corner of your web browser at "Extensions" (the puzzle icon).
Load a tree so that it's showing on Ancestry, MyHeritage or FamilyTreeDNA. Then click the One2Tree icon and press the Go!-button.
If you have bought a subscription of One2Tree you need to login with your Google-account that you made the purchase with in order to get access to the full version. Do that by clicking the "Login"-button.
If you do not have a subscription for the full version you can get that at our website.
Please contact us by email at nordeboapps@gmail.com if you have any other question.