Plants and wooden elements could be added, but the kitchen is pretty dated and unless you can paint the units there’s not much you can do, especially in a rental.

As Sonia says, just adding some plants may lift it but tbh it is beyond help and needs more than a bit of tlc, if you're renting it, it would be a waste of your time and money to do anything as it really wants starting again from the ceiling down to the floor and thats your landlords job.

Under cabinet strip lighting is cheap and temporary, at least here in the U.S. and makes a big difference in the evening. It creates a warm glow that puts the focus on the countertops, where you could have plants and stylish small appliances.

We totaly agree with what other Houzzers here above have mentioned. We would may be add a Vintage runner rug covering a fair lenght of the kitchen, it will give it extra warmth and coziness

Thank you all so much! I will work around the lighting strip and plants as recommended 👌