Can there ever be a maximum number of web pages or can the internet handle an unlimited number of these pages?
So long as there’s a server that can host more pages, there’s room for more of them. A server is a computer that has software that allows it to deliver webpages that people request. Now where you’re gonna put the servers is another issue…
There is a limit to the number of routable IP addresses on an IP network (which is what the Internet is.) IPv6 will fix this by increasing the address space by several orders of magnitude.
An IP address refers to a network interface on a computer.
Any Internet-connected computer can theoretically host an unlimited number of web pages; the limitations are only in bandwidth and storage capacity.
Is there also a limit to the length of a URL? If there is, that would theoretically limit the total number of pages. It would be ridiculously large, in any case.
Some limit it to 32kb characters, though this is a OS limit, not a browser issue, any modern OS can handle virtually limitless, even at 32k, I do not think there is enough space on the planet to hold all the servers 
Some registries will take 64 characters for a domain name, and they’ve expanded the character set to include non-English characters, so the number of combinations of domain names far exceeds the number of routable IP addresses. However, even a limitation on IPs doesn’t limit the number of pages on the net. A single IP can hit a server farm generating pages from a back-end database that could produce pages of near-infinite variety.
Part of this is semantics: what do you consider a page? If I put up a single script that displays a (pseudo)random 6-digit number, does that count as a single page or a million pages? This is analogous to a single gateway page that generates pages from database just like showthread.php on this site. Is showthread.php a single page, or does every thread on this site count as a page?