Whenever i try to setup my wifi router as wireless router then i try to add network connection via PPPoE my net stop working, and i'm sure i put the correct info and i contacted my ISP (te.eg) but wit

I get very slow wifi internet speed with Archer's wifi against my modem's wifi router. my speed is 30mb/s and i get around 25 in modem's wifi but i barely hit 10 with tplink's wifi... I use the 2GH/z