Hi dayanon, and welcome to CC!
You're certainly welcome to comment on any thread, though we have a friendly-critical term for older threads which people 'resurrect' by commenting on them: zombie threads. You can see the date of the last post in the upper-left corner (in this case, the most recent prior to yours was May 26, 2015). At least in the Singles forum, you're generally less likely to receive said criticism if you keep your comments on track with the first page or two of threads. You may start a new thread too.
You're certainly welcome to comment on any thread, though we have a friendly-critical term for older threads which people 'resurrect' by commenting on them: zombie threads. You can see the date of the last post in the upper-left corner (in this case, the most recent prior to yours was May 26, 2015). At least in the Singles forum, you're generally less likely to receive said criticism if you keep your comments on track with the first page or two of threads. You may start a new thread too.