What is the difference between a Stream cipher and a Symmetric Encryption algorithm? According to the Tag definitions:

Stream Cipher: A stream cipher is an encryption algorithm which encrypts arbitrary length plaintext, using a key. Some stream ciphers generate a keystream from only the key, which is then XOR-combined with the plain text, others feed back plaintext or ciphertext into the algorithm to create the keystream.

Symmetric Encryption: Symmetric cryptosystems assume two communicating entities share a pre-established secret key.

What is the difference between these two terms? Is there a particular situation that would be more ideal for a Stream cipher instead of a Symmetric encryption algorithm (or vice versa)? Or are these two simply different terms for the same concepts?

Follow up: ChaCha20-Poly1305 is identified as a stream cipher. Is AES/3DES also a Stream Cipher?
There are multiple ways to do symmetric encryption. The two most popular ones are block ciphers and stream ciphers. So stream ciphers are a subset of symmetric ciphers.

AES and 3DES are block ciphers, not stream ciphers. But if you use them (or any other block cipher) in CTR mode, you can create a stream cipher out of them.

ChaCha20 is a stream cipher, Poly1305 is a MAC (message authentication code) algorithm. Together, ChaCha20-Poly1305 form an authenticated encryption scheme.