Cannot use Trezor with metamask

Hi I hope someone can point me to a good tutorial. I want to use Trezor to enable metamask transactions, but after watching some videos I still cant do it.
When connect my metamask and choose an account to add a list comes up and I am able to add one. But I understand that this is a Trezor account…not my metamask one. So there is no eth in it and to transfer Eth from my metamask eth account to my Trezor metamask account costs a lot of gas fees. Is there any way to link these accounts?

So if I want to sign transactions in a Dapp, I need to connect to the Trezor account on my metamask or am I missing something here??? I would like to use other chains like Harmony or Avalanche C chain but cant understand how to do that either, because of the same problem of linking the accounts.

Sorry if these seem like dumb questions. I need some very basic instructions…Thanks in advance.

You don’t want to link the accounts.

I mean, you obviously want to do that, but the result is not what you want.

Your funds in the Metamask first account are controlled by private keys stored on your PC. If you get infected by malware – or if you have been infected by malware at some point in the past – those private keys can already be compromised. A hacker could drain your accounts tomorrow. That is why you’re getting a Trezor, right?

Now, there’s nothing you can do for those private keys. If they’re gone already, they’re gone.
(Even if you loaded them into Trezor (which is possible but strongly discouraged), a hacker might already have them. Trezor is not a magic padlock. It protects your private keys from being stolen – but if they’re stolen already, there is nothing Trezor can do.)

The thing you need to do is get new private keys that have never been exposed to malware. That is what Trezor did for you.
Unfortunately, new private keys mean new address, and you need to use the old private keys to move your funds to this new address.

So unfortunately, you’ll need to pony up for the gas fees in order to take advantage of Trezor.

need your help

Thanks a lot for your reply. I have not been infected by malware…as far as I know. Hopefully!

So I understand from what you have said that I have to use the Trezor account on my metamask and put funds in it. But if I have already interacted with a Dapp under my old metamask account then it will not recognise this new address and I will appear as a different user.
As I had asked: are there any tutorials on the process of using Trezor with metamask. I don’t know if I can use it with different chains. I don’t use Eth much, it is more Harmony and Avax. But i don’t know if I can add these. And if I do then I run into the same problem of appearing a different user so I would not be linked to my original account if i connect ed to Defi Kingdoms for example.
I had thought that the Trezor could be used to sign transactions for all accounts on the MM, but obviously don’t understand it properly. Which is why some tutorials would be good.