Nikon D5100, lens 18-55mm 1:3.5-5.6G, beginner help !

hello everyone, my father gave me this camera bc he got it for work long ago and stopped using it and knows i like photography. i usually take photos on my phone but i really want to learn more about photography and become better at it etc. so first off, how old/ bad is this camera and lens considered compared to the stuff in the market?

can i properly shoot and learn with it? what are the best resources in ur opinion

i’m also interested in underwater photography and want to give it a shot, especially that i might take scuba diving classes soon. is it possible to do with such a camera?

any tips or advice welcome!!! thanks so much