Do you have any photos?

Art and plants will offer the "liveliest" impact. Inexpensive art can be DIY. So many ideas out there, from repurposing inexpensive thrift store finds to creating your own. Or maybe you have a huge blank wall crying out for a mural? Do you own or rent? That might determine the scope of your decor options.

What's on the windows? I am guessing blinds. Proper window panels will cozy up any space.

It sounds like you liked the decor at the Airbnb; if so, can you link to the property? Or maybe to other images of decor that you find appealing?

How much furniture do you have? If you came from an Airbnb, I'm guessing you started with nothing, but you've probably acquired at least a few things for the new place. Are you still looking for advice choosing big furniture pieces, or are you just looking at the items that pull a room together (curtains, rugs, art, etc.)? Photos would definitely help.

Hi guys. Here I have some pics of the living room.

That's the desk where I'm doing my home office.

I get the advice from the previous posts, thanks a lot.

Seems like plants could do the trick (although I already think plants might be expensive haha).

It's a bit tricky because it's a rented apartment, I don't own the place, I rent a room here with other 3 guys, but they don't mind the decoration much.

So I could maybe buy some stuff I'm going to keep after I move somewhere else or whatever.

The surfboard for example is mine.

Thanks

It's a bit tricky because it's a rented apartment, I don't own the place, I rent a room here with other 3 guys, but they don't mind the decoration much.

So I could maybe buy some stuff I'm going to keep after I move somewhere else or whatever.

Yes, buy stuff you love to take with you when you move to your new place. (About "stuff" though: There is often a fine line between meaningful decor and stuff that's a pita to maintain and a nuisance to move. If an interest in collecting is triggered, make sure your collection is purposeful for you.) I think this is a perfect time for you to discover what makes a space "home" to you. As @cawaps said, recall the Airbnb to see what you found so appealing there. Browse other pictures of interiors to "analyze" them. What makes the spaces welcoming to you? It could be anything: a sense of order to things, a harmonious colour palette, the wall decor, the greenery, the light in the space... There is no right or wrong to this stuff. It's about discovering what resonates with your senses. Usually though, interiors appeal to us when they're cohesive. They "make sense" to our eye.

Back to your pictures now. Pics aren't always reliable in capturing a sense of space but what struck me first in your pics was two things:

1) the lighting is cold and glaring (could be the pic renderings and perhaps it feels better irl?)

2) the furniture, especially the living room seating, is too large for the space

The lack of decor cohesion is practically a given if your roommates don't care for that stuff. And if they did, they might have different tastes so you'd all be dealing with compromises. It can take a lot of effort and tweaks to "finish" a space for a family or a group of roommates but it need not cost a fortune. If your bedroom is to your taste and you now want to improve the living spaces, here are some ideas:

-plants don't need to be expensive. People with green thumbs often give cuttings to friends. Look on Craigslist and FB Marketplace. Bet you'll find people giving away plants during moving season. Grow your own from seeds? A small herb garden in the kitchen? Inexpensive ugly plastic pots can be spray painted or covered in inexpensive jute or fabric.

-Consider making the entrance more welcoming for you. That's the wall with the small console table and frog art on the floor? Find inexpensive art to dress that wall and make you smile every time you come home. There are LOADS of talented artists on Etsy offering their art in digital format. It can be printed at an office supply store, for example, and framed inexpensively. No money for a large piece? Create a gallery wall from smaller pieces collected over time. I recently discovered Dan Hobday Art on Etsy from a Ytuber. Affordable and instantly downloadable abstract and figurative pieces. Just make sure the print sizes work for you because he's based in London and works with their paper sizes. I do believe he can resize prints so worth asking. Would a closed storage piece in the entrance make more functional sense than the console table? If so, take measurements and scour thrift stores, estate sales and the secondhand market (Letgo app, etc.) for an affordable cabinet or chest. Depending on where you live, you might find a neighbourhood stroll on thrash day evenings to be a goldmine (skip upholstered stuff but consider wood or metal pieces that can be easily transformed with paint and elbow grease).

-Fine tune your desk area. What's working for you there and what's not? If a lamp is needed, look at table lamps rather than desk lamps to minimize the office in the dining room look. Do you have a Target or HomeGoods nearby? They have loads of stylish and inexpensive table lamps. If the space is cluttered, find ways to get stuff out of sight. Magazine holders, boxes, drawers... Let's face it, clutter never elevates a space. :)

Loads more ideas for your space but hope these give you a start. Don't know how long you'll be living there but "home" is rarely created overnight. Patience, imagination and resourcefulness go a long way.

Hth. Good luck!