Connecting tp link archer c24 from modem?

Question

TP Link

Hello, my relatives have a picotel pu-e710 modem (as I understand they have a phone line) and the computer is connected via pppoe (that is, they enter a login and password).
They bought a tp link archer c24 router and then the question arose how to connect it?
As I understand it, we insert the cable instead of the computer into the router, and from the router we insert the cable into the PC, but the question arose how to set up TP Link so that the login and password are entered