I know it's kind of a random question to ask for tech troubleshooting here but this is literally the only place on the entire internet that isn't infested with condescending tech-bros, so I'm doing it anyway.
I'm also about to fuckin' ramble, and networking terms go over my head, so anyone who's answering please talk to me like I have no idea what anything means.
Alright, so I have xfinity (fuck monopolies, fuck capitalism), and the internet frequently cuts out. I am told that before we had our own modem + router + extender setup (that is, not the one xfinity provided, but a modem and router and extender we bought ourselves) the internet did not cut out quite so much. I'm not entirely sure I buy it, but it's not like I can fix xfinity's trashfire infrastructure that they have literally no incentive to fix because they are the only actual choice in the area.
Internet very frequently lags enough to kill the enjoyment of whatever game I'm playing, and a couple times a month or so the internet in the whole house just dies. Sometimes rebooting the modem and router fixes it, sometimes it doesn't, sometimes - and this is the part that boggles me the most - the internet will work when you connect through the wifi extender, but NOT when you connect directly to the router's wifi... the same router that the extender is connected to. I assume this has something to do with IP addresses, but again, I don't really know how IP addresses work, how to change mine, or whatever. Frequently some sites / services will load but others won't. Lastly, apparently we are paying for more powerful internet than our modem supports, but I don't know if getting a more powerful modem will actually stop the internet from crashing so much, and since being alive costs so fucking much I don't want to blow like $200 or whatever on a more powerful modem if it's not actually going to fix anything.
Someone please help me; I am an internet-addicted fiend and nothing erodes my psyche more than when I'm about to finish the runback on this fuckin Zangief I finally figured out in a first to five set and then suddenly xfinity pulls the plug on the final round.
Anyway rambling complete... for now.
A third party router can help improve the stability of wifi connections since the ISP provided routers are always crap however a lan connection shouldn't see that much issue. If lan is down then the ISP is likely the one that sucks. If its wifi only thats down then the router sucks. But this isn't necessarily always the case.
I had massive issues with our shitty copper lines in britland where my bandwidth would slowly get slower and slower until it was unusable. I'd open a support ticket, they'd fix it after a few weeks then it would slowly start dropping again. Didn't matter what router was used the only thing yhat resolved it was when fiber lines got installed and I switched to that.
A third party router may make your wifi more reliable but wont do shit against actual outages. I have heard stories of virgin media routers being so crap that they themselves are the point of failure causing what would appear to be an outage.