recently I ordered 2 replacement remotes : RC66RX

Ok, RC6X series is the white universal for the 1st gen Genie (HR34) or older models (non-Genie). That will use the more manual option to program it for the TV. If the TV is already on the correct input, you could pull up those instructions on screen (assuming you have the correct model that remote is for).

https://www.directv.com/support/article/000092856

Program Universal remote for an HD DVR or HD receiver

1. Press MENU on your remote.
2. Select Settings > Remote Control > Program Remote.
3. Choose the device (TV, audio, DVD) you wish to program. If you don’t see your TV or device listed, use the code lookup tool to find the 5-digit code.
4. Follow the on-screen prompts to complete programming.

For whatever reason, the TV INPUT button is programmed separately (after you've got it working for the TV). The newer RC7X series doesn't have that quirk, but is only for the 2nd gen Genie (HR44) and later models.

Change your TV’s input source

1. At the top of the remote, slide the mode switch to TV.
2. Press and hold the MUTE and SELECT buttons at the same time. Stop when the green light at the top of your remote flashes twice.
3. Enter 960 using the keypad on the remote control. The green light should flash twice again.
4. At the top of the remote, slide the mode switch to the DIRECTV logo.

(edited to add)

Being that is a 4K TV, it might be too new for a completely compatible code for the older series of remotes.

https://www.directhd.tv/directv-remote-code-lookup/ 

Older style DIRECTV remote (RC60 Series):

1. HOLD ‘SELECT + MUTE’ at the same time until light blinks twice at the top of remote.
2. Using the number key, enter your TV code. Wait for the green light on top of the remote to flash twice – this means code was accepted. (see code list below)
3. Aim the remote at your TV and press the “PWR” key once. Your TV should turn off. If it does not turn off, repeat the steps above, trying a different code until you find the correct code