I have read all the way up to chapter 8 in the manga series called "Absorb: Ability", but I cannot find the 9th chapter anywhere on the internet. Does anyone know where I can read this manga? It does not have to be in English.
You're probably going to have a pretty hard time getting a hold of this legally. As far as I know, there's no legal digital distribution of the manga, so you'll need a print copy. While you may be able to find pirated copies online, we won't help you do so here as per our site policy.
Absorb; Ability was never especially popular in Japan. There are 2 volumes, each with 6 chapters, so you'd only need the second volume. The series ended in 2008, and the volumes have long been out of print. There's no licensed English release (confirmed by Baka Updates), and given the length and popularity licensed releases in other languages are also very unlikely. So you'll have to get your hands on the out-of-print originals, which means looking to the pre-owned market. This is unfortunately not easy, especially if you don't live in Japan.
There are a couple online Japanese stores carrying it right now. Amazon.co.jp has it, and there are some available used copies for very cheap. It's also on Suruga-ya. Both of these stores will only ship domestically in Japan though. You can use a proxy or forwarding service you're familiar with to get around that if you're willing to pay somewhat more.
Unfortunately I couldn't find anywhere that would ship internationally without a proxy or forwarding service, so if you aren't going that route your best bet is to check ebay regularly and hope it appears, which is honestly not very likely. Relatively obscure series like this tend to require jumping through some hoops to get your hands on.