FYI: The browser is a program (=software) that is installed on your computer or phone. Your bookmarks are stored on your computer except you use a cloud service (not recommended). The browser will not very likely be attacked/killed. You can have several browsers installed at the same time. Search engines (google, bing, DDG etc.) are websites with the purpose to find other websites for you when you enter search words. You only need to search for websites you haven't already bookmarked. You can use several search engines if you bookmark these. Some browsers have a default s  4fca  earch engine bookmarked "for you" that has a seperate field for your search entries or reacts if you enter search words instead of a link. You need not to use that default search engine (or configure the browser touse another one). You always use web adresses as a URL (like "https://voat.co"). The IP address of the site will be added by a DNS server (that has a large table for that). When the internet will go down, it is the most likely thing to happen that this will be done by taking out the DNS servers. Without a DNS server you can use only a few websites by using the direct IP of the site. You must know the IP before (if no DNS available) and not every site accepts this (Voat also doesn't as far I tested that). So you should know several DNS servers you can enter in your internet settings in that case to try to get online again. A good VPN has it's own DNS server.  And always backup important files and your bookmarks offline.