There are several ways to find NFT drop, the most obvious one being a NFT drop Calendar such as NFTCalendar.wiki
So the easiest way is to check the NFT Calendar. There are other methods to find NFT drops, let's have a quick mention about these
Yes twitter is a treasure trove or information the issues comes with filtering out the noise. That's where hashtags are a very powerful tool. Hashtags are essentially a form of metadata designed to organise masses of data.
Using hashtags one can filter out messages that are specific to your search. Think of it as google for social media. The most popular hashtags for NFT are the following : #NFT #NFTs #NFTGiveaway #NFTColleciton #Opensea #NFTArtists
Using these hashtags one can quickly filter out the noise and follow twitter profiles that are promoting NFT drops, and also the NFT drops themselves.
Discord is essentially a huge chatting service, popular with gamers as it allows voice chatting in a group setting, is fast and highly customizable. The discord platform allows owners to create bots like mini programs that can help make the server more efficient and give users more content. For this reason discord has become popular with NFTs as many NFT projects are about community.
When on discord you will find channels dedicated for other drops; these shill channels are where you can check what other NFT drops are happening. Join their discord with a single click and learn more about the drop.
In summary, to find NFT drops you need NFTCalendar.wiki Twitter and Discord.