Changing my Router.

[scotsmac]

Firstly Hello everyone, and big thank beforehand for any up and coming help.
A big hello from Scotland.
I live in Scotland and my WyFY is provided by SSE, on a package.
Now last week I was having problems getting my LG Oled Tv to mirror my MacBook Air through Air play2. Funny enough my Iphone 7 the mirroring was perfect , but from mac all out of sync.
After few hours with apple tech we worked it out that my Router was not sending a strong enough signal. ( All in same room, and little distance, and no walls in between ). We sussed this by feeding the Wyfy signal from my phone data to mac , then airplay from Mac to LG Tv and all was perfect.
So basically I need upgrade my Router, hopefully one with an antenna on top.
Now Im not sure If my current router, is also joined with a combined Modem, or if the Modem is separate. I am waiting for SSE my provider to let me know if my Modem is separate or joined . ( Is their any easy way to find out myself ) ( I am NOT a tec wizard, so treat me like a dummy )
Now my main Question. If I upgrade with new Router. Is it just as simple as unplugging the old one, and plug in the new one ? Do I need change Passwords on TV and other items ? Or is my WYFI a set password ?
What Router do you recoment without spending to much ?

 

[PP Mguire]

1: if one works, the other should have as well.
2: Do you have cable? Easy way to tell if it's all one unit is look in the back. Is there coax going into your router? If so, it's all in one.
3: You don't need to unplug the old one, only disable the wifi on it if it's an all in one. If the modem has an ethernet port all you need to do is plug an ethernet cable into that port, then plug into the WAN port of the new router.
4: You will need to set your own wifi credentials in the new router. You can match what you currently have, or change it to something else.
5: Define without spending too much. Decent routers start around 75USD, will be different over there.