yes, they can. noopept - sublingually 10-20 mcg, aniracetam - 750 mg with fish oil. Take a choline source as well - DMAE, Alpha GPC, CDP Choline... Add L-theanine, caffeine and Huperzine- A for better results.
phenibut isnt good for you. it can help anxiety the same way alcohol or benzos can, but it also can cause dependency and withdrawal just like those drugs. it's sold along nootropics but it's more like a recreational drug than a noot
Noopept and Aniracetam dont really have a thing for you to feel associated with them (arguably, Aniracetam can have a calming effect if you're an anxious type, but it isn't obvious to most people). You will see their effects in your memory retention and scope of thought more than you will "feel" them. Phenibut is a different matter, it is pretty much a legal recreational buzz.
Phenibut probably resembles benzos in what it will make you subjectively feel (to me, it isn't as sedating as benzos but it does calm anxiety and lift your mood). Aniracetam and Noopept are things that wont have an obvious benefit at first, but over time you will probably find your recall and focus improve. I had sensory sharpening effects from Aniracetam (I get that from all racetams, though, where my vision and hearing become clearer -- or at least, my perception of my vision and hearing becomes clearer, I dont mean to imply that the organs responsible for those senses change or anything)
If you're depressed, please be careful with Phenibut. It takes 2-3 HOURS to begin working, and as a person who has depression issues, I can tell you that once you begin to acquire a taste for the sensation of Phenibut you might trick yourself into thinking that it isnt working fast enough and dose higher. DONT do this. Long term Phenibut use carries with it some miserable withdrawls that will make you a whole lot more miserable than you may already be. Please go easy with Phenibut and keep your dose within reasonable levels.
I've taken all three of those together before. Noopept is like 20mg, I was taking up to 30 per dose. Aniracetam I would take anywhere up to like 4 grams or so I loved that stuff, but I'm like 280lbs. Haven't used it in a while though.