I cannot connect my old and new Mac

di3101 wrote:

when I use migration assistant my new Mac don't see old Mac

Try one of your backups and compare your results...

The most trouble free way to move to a new machine, is using the Setup Assistant on the initial boot of a brand new machine— you have one shot here. Set up your MacBook Pro - Apple Support

The second best way is use the Migration Assistant.

How to move your content to a new Mac Move your content to a new Mac - Apple Support

If both computers are using macOS Sierra or later, place them near each other with Wi-Fi  turned on.

When you do, they will create an Ad-Hoc network and attempt to transfer as fast as possible using that ad-hoc network.

di3101 Said:

"I cannot connect my old and new Mac: when I use migration assistant my new Mac don't see old Mac"

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Uninstall Security Software:

Security Software would block port accessibly. So, if it is installed, uninstall it (using an uninstaller). Security Software just gets in the way on a Mac, and this is a pur example of how and why.

One more thing to check, is that you are running Migration Assistant on the old Mac while you are attempting this transfer, and that it has taken over the old Mac and focused the old Mac on nothing but the transfer.