Better extractions

Good morning everyone! My wife and kids bought me the Breville Barista Express two years ago when I was diagnosed with pancreatic cancer. I am doing very well now! I am by far not a barista but I have enjoyed my machine every single morning since it was given to me. My problem started a few weeks ago, pressure not building up. I have fixed that with the help of google and some videos. What I want to fix now is the crema. It is definitely not up to snuff. It may be something as simple as my beans not being fresh enough. Although they do have a great smell and oily appearance. My wife gets them from Kroger. They are Starbucks French dark roast. She used to get me the Starbucks espresso bean but it’s not always available. I’m a simple guy looking for some simple suggestions. FYI I have tried drinking just a shot of espresso but it’s not very good at all. Thank you in advance!:purple_heart: