Some tips to help feel like you're in the 2010s.
First, you can decide what part of the 2010s you're stuck in/ prefer. This isn't technically necessary, as you can prefer the 2010s as a whole. But it can help to have a time frame. The early 2010s and late 2010s had different vibes due to the rapid improvement of technology and the fast paced trends. You don't have to pick a specific year(s) but it can help.
Also optional, but you can decide what "subculture" you're a part of. Are you a hipster, a fandom blogger, or a scene kid? Or maybe you're an ipad kid. You can be whatever you identified with in the 2010s or maybe you can try being something new. Maybe you were an ipad kid but want to try being a tumblr hipster. Or maybe you can be into all the things.
Look into memes that were big in the 2010s. Memes changed rapidly over the course of the 2010s. A good thing to do is look up Vine Compilations on youtube. Vine was huge and is both a representative and an influence on 2010s style humor and internet culture.
Listen to music from the 2010s. Listen to pop songs from the time. Look up playlists on youtube and spotify. Listen to nostalgic nightcore playlists or try to find videos that were posted from the time.
Look up fashion that was popular at the time. You can even try thrifting and see if they have any clothes from the 2010s or that looks like it could fit in with the 2010s.
If you are able to, try seeing if you can get any technology from the 2010s. Try to see if you have anything from the time still lying about, like an old 3ds or ipod. You could even try checking ebay to see if someone is selling their old technology.
Try playing video games from the time. For certain games it can be harder because they might've updated and aren't quite the same anymore. But try seeing if there are any archives of older versions of games out there or any fan projects that recreate the old versions of the game. I know Minecraft for example has an option where on Java you can play the old versions of it.
Try to stop using Tiktok (if you even use it...im a tiktok hater lol). While tiktok existed at the time in the form of musical.ly, it's very different now. Tiktok is where a lot of newer trends and memes come from. Tiktok is very 2020s. It can break your immersion and remind you of the current time. If you're anything like me it will make you feel old and out of place lol. You don't have to follow this tip, especially if it doesn't bother you or you're perma2020s. It can also help to follow "older" creators (older gen z and millennials), especially if they post nostalgic content or about their experiences.