Wa alaikum assalam warahmatullahi wabarakatuh,

You can use it only if you are not sure it’s copyrighted. If you are sure it is then don’t.

Assalamualaikum wa rahmatullahi wa barakatu, I found a nice photo of nature that I would like to use on my website. The photo is widely circulated, however, as with many photos on the internet, I do not know who the original owner is or if the image is copyrighted. Is it permissible for me to use this image despite not knowing this info, or should I refrain from using it? Jizak Allah kheyr