Can anybody help please

I have a shop using Opencart 1.5.6.4 I would like to upgrade to the latest version but I can't seem to find a comprehensive tutorial of how to do this. Could somebody direct me to the best tutorial for this? I tried following this https://randemsystems.com/support/openc ... n-2-1-0-1/ but it didn't work.

I have lots of products that I would need to be migrated over to the new version.
Many thanks in advance.

there is none, OC v.2 is a different version, and uses different Extensions and Themes.
But in the OC ExtensionSection, if you search for UPGRADE,
you will find professional assistance, preventing you from screwing up. And
since you seem to have a busy Shop, you probably can afford to spend a few Bucks,
to make sure...
Good Luck
Ernie

Yes, I was thinking about this. Is there a way of knowing who to trust?

well, I would probably select one of the major Players, when it comes to such,
and sure not on one, hiding behind an anonymous Mail Account and/or no identifiable Site.

But those two Gentlemen probably belong to the TopTen, because, it's not done by upgrading
the OC Software, if you use Mod's, they have to be reworked as well:
https://www.opencart.com/index.php?rout ... n_id=20437
https://www.opencart.com/index.php?rout ... n_id=21575

But there are others as well, I just don't know about, since I don't use that 'knowledge about', it's overdue
anyway already, should I ever move up.
Good Luck
Ernie