The Message is Happy Holidays
10 - [A-z] (-2) is
H because 8th letter in the Alphabet ( 10-2 is 8)
255 - #beginningfirst00
255 converts to ff and bf is the intials of before first #ffbf00 is the colour Amber
15 - Period.
PHOSPHOROUS which is 15 on the periodic table.
0 - You forgot one. You forgot one. Since every beginning has an end, let's pave the way.
Basically this is just hinting at the letters P and Y. Hap Holidays needs those two letters to complete it. Letters P and Y pave the way.
1 - I'm on repeat.Thanks to lxop for this
H is the answer. Because it is 1 letter and it is a repeat of the first puzzle.
7 - Zelda's legend. I hear Link is quite the musician.
This hints at the 7 Letter word OCARINA which is a musical instrument and part of the title of a Legend of Zelda game.
5 - Lester lists the lesser lesson last.
The letter L because it appears 5 times in the sentence.
64 - 08,21,56,W
Hinting at the song Reykjavík (64° 08' N 21° 56' W) by Kristjan Hrannar. Maybe the word you are looking for is ICELAND.
44 - June 5th Day.
1944 June the 5th was Eisenhowers selected date for the D-DAY invasions.
33 - “For him?” shouted Snape. “Expecto Patronum!” “After all this time?”
A passage in Chapter 33 of the Deathly Hallows. ALBUS Dumbledore says "After all this time".
8 - Tulips on a tree?!
You are probably referring to the 8th letter of the word KENTUCKY which is Y, the tulip tree is Kentucky's state tree.
21 - Monday, the sun will fly south for the winter.
Monday 21st of December 2020 is the Winter SOLSTICE.
And so you have
H, AMBER, PHOSPHOROUS, P and Y, H, OCARINA, L, ICELAND, D-DAY, ALBUS, Y, SOLSTICE.