Learning Sanskrit
पाणिनीयधातुपाठः – https://ashtadhyayi.com/dhatu/
अष्टाध्यायीसूत्रपाठः – https://ashtadhyayi.com/sutraani/
Sanskrit Dictionary
VS Apte – https://dsal.uchicago.edu/dictionaries/apte/
Andhra Bharati – http://www.andhrabharati.com/dictionary/sanskrit/index.php
Spoken Sanskrit – https://spokensanskrit.org/
Upanishads
Website 1 – https://upanishads.org.in/
Website 2 – https://www.upanishads.iitk.ac.in/
Website 3 – https://advaitasharada.sringeri.net/
Website 4- https://sanskritdocuments.org/sanskrit/upanishhat/
Website 5- https://advaitasharada.sringeri.net
Purana
Markandeya Purana – https://archive.org/details/markandeyapurana
Linga Purana – https://archive.org/details/KurmaPurana/Ling%20Purana
Vyasa Smiriti –https://archive.org/details/vyasa-smriti-m-n-dutt
Taittiriya Aranyaka – https://archive.org/details/taittiriya
Ramayan –https://www.valmiki.iitk.ac.in/
Ramcharitmanas – https://www.ramcharitmanas.iitk.ac.in/
Work of Adi Sankara – https://www.sankara.iitk.ac.in/