If its a 2005 and you took a 16 yr break I'm guessing the group hasn't seen a lot of use (you didn't mention the groupset on the bike -Ultegra?). So other than tubes/tires maybe take it to a reputable local bike shop and let them tune it up or at least look at it and make recommendations. Thinking cables might be good to change after all that time. If its Shimano then in 2005 you had Dura-Ace, Ultegra and 105. In 2021 you have Dura-Ace, Ultegra, 105....and the lower groups. Things have changed and groups have gotten lighter over time but as mentioned if there's not a lot of wear on the group its probably still good.