Here are some useful and informative links to reliable sources to learn more about the UAP/UFO Phenomenon:

UAP Guide - A 15-minute introduction to unidentified anomalous phenomena (UAP)
The Debrief
Echo Congress - Paris
UAP Check
UAPDb - Unidentified Aerial Phenomena Database

Podcasts:

Disclosure Team - Vinnie Adams
That UFO Podcast - Andy McGrillen, Dan Zetterstrom
Need to Know - Bryce Zabel, Ross Coulthart
The UFO Rabbit Hole Podcast
WEAPONIZED - Jeremy Corbell, George Knapp
MERGED - Ryan Graves
LEHTO FILES - Chris Lehto
THE GOOD TROUBLE SHOW with Matt Ford
TOE - Curt Jaimungal

Documentaries:

The Phenomenon - James Fox
I know what I saw - James Fox
The Ariel Phenomenon - Randall Nickerson
Moment of Contact - James Fox
7 Days With The Man Who Confirmed Aliens Exist (under oath) - YES THEORY
UFO Whistleblower Dave Grusch Tells Me Everything - Jesse Michels

Scientific Projects and Institutions:

The Galileo Project - Harvard University
UAPX
SOL Foundation
Unidentified Anomalous Phenomena Integration & Outreach Committee
Scientific Coalition for UAP Studies
All-domain Anomaly Resolution Office (AARO)
Sky360
UAPcaucus
Witness Citizen
Disclosure Diaries
Declassify UAP
Paradigm Research Group