The 2-0 win saw City reach the Champions League round of 16 thanks to goals from Erling Haaland and Rayan Cherki.
“The first half was better than the second, but in the second half there were more chances than the first. A lot of things to improve,” said Guardiola.
“We’re really pleased to finish top eight considering how the Champions League has become.
“When I started 16 or 17 years ago, qualification was not as difficult. Today, every team is really, really tough, and I’m really pleased and hopefully we can arrive in March in our best.
“We started really well and had chances. We had no proper holding midfielders there. Jeremy (Doku) and Omar (Marmoush) were excellent, but we had incredible chances and maybe we (could have) needed more goals to qualify.
“But I’m really pleased because we have long weeks (until the Round of 16) and we need it. Not just that, that we’ve already qualified. Hopefully in that moment we can arrive better.
“Look how many incredible teams are out of the top 24 and how many are not in the top eight and still it’s the youngest team we have played in my years here in the Champions League.
“It’s a process to learn and hopefully Rodri, Marc (Guehi) and (Antoine) Semenyo will be back when we are there. That’s good news.”