Cpanel Login issues Then Linksys Router issues

[#1]

Hello, I am running a bog standard broadband connection through a TP Link Archer D20 router. Recently I have had dropping issues. then I have been asked to access email via  Cpanel. It wont let me login. the stae manager had logged two issues and been told that the ISP  is not being blocked and the issue is with  my ISP or my router. So my router is a bit old. 

So I buy a new one a Linksys MR 6350. I have spent all day  trying to get this to 'talk' to my broadband  via an awful app they make you use. but no, it cannot pick the broadband and also there are issues when I input connection data DNS etc of gateway  which tell me that they are not correct or valid. 

Someone please help! If you cant suggest something for the Cpanel then something for the router. is this to do with broadband connection or Plusnet?

[#2]

You are aware the Linksys MR 6350 is a router only and will not work without a modem ?

[#3]

Ok so I have to buy a separate modem? I though this was just to do with dial up type accounts? 

[#4]

Some routers have the modem built in. Some don't. Can apply to both ADSL or Fibre lines.

As you've already found out, It really does pay to do the research before committing to buy. I used the Draytek Vigor 130 Modem but it can be pricey - you get what you pay for though.