Guinea pig help

[Elohi]

I just bought an adult guinea pig for my daughter. He is older for a gp I think if his age is correct. They said he is 4.
I need advice on optimal care for him so the remainder of his life is as good as it can be. Best foods. Best bedding. Advice on exercise. Bathing. Ect, ect.
Thanks in advance.
He is really cute but fearful when being picked up at first. Also his coat doesn't feel very healthy to me so I'm going to assume his care hasn't been the best.

 

[Laura]

hay and guinea pig pellets.. NOT rabbit.. they need vit C .

 

[Elohi]

He has some guinea pig food pellets that have multivitamin, including c.
I haven't tried yet, but the previous owner said Romeo won't eat oranges.

The guinea and my daughter are over at her dad's house for the weekend. My daughter is completely smitten with him. Her dad sent me a couple of pictures. He said that Romeo follows her around like a puppy.