Recently I purchased the bloodborn the old hunters dlc on one profile, but when I'm on my other profile, it doesn't say I've purchased or installed it. I just need to know if the dlc I bought on one profile can be used on my other profile.
Yes, the DLC should be available on your other profile.
You need to set the profile that bought the DLC, as a primary profile. Therefore all profile on the same console can gain access to the DLC.
To set as primary profile: (Must be done using the profile who owns the DLC)
Settings > PSN > Set as Primary Account