off topic does a dog know that he’s being loved?

so i always had a fear that i i got a dog, the dog would be depresssed or unloved or soemthing ... I do show my maltese poo a lot of love and my family too. he’s little white fur dog , he’s an indoor dog. i know that i show him a lot of love and kiss him and cuddle with him, but do they know that? Do they know that they are being loved by us? Also do dogs have feels? like us humans? Like are they sad, depressed, mad, Happy just like us? or are they just like whatever ?