No. It is not mandatory. As long as they are spelled right, they should work.
The font is Didot, and you need to stretch it to make it look like it
Your question is confusing. If you need to change the style of the text, you need to use style/CSS.
You don't need to, just look at the file format. TTF is TrueType font, .jpg would be a type of bitmap font.
C++ doesn't understand the notion of a font. To work with fonts you will need a graphics library. The library will provide the methods required to change font sizes.
It will depend on the website. Different sites will need to present the data differently, so what might be a good size on one site may not be right for another site. As part of designing a website you need to choose what font size is best to use. So there is no single answer to the question.
All proper nouns should be capitalized but all words are capitalized at the beginning of the sentence.
Yes. In English, the names of languages are always capitalized.
No. Only the first (or only) letter of chemical abbreviations (O in this case) needs capitalized, but not the names of chemicals when they are spelled out.
Proper nouns, names and the begging word for every sentence
Yes, "Koala" should be capitalized as it is a proper noun referring to a specific type of animal.
Generally speaking, numbers do not need to be capitalized unless they are part of groups' names or similar.
You can find a font similar to the one used for the 1980s Doctor Who episode names on various font websites or through a general online search. Look for retro or sci-fi fonts that resemble the distinctive typography of the show's titles from that era. Remember to check the font licensing terms before downloading for personal or commercial use.
The word evolution does not need to be capitalized.
No, coral does not need to be capitalized.
Cannabis shouldn't be capitalized unless it's at the beginning of a sentence because it's not a proper noun. Cannabis does need to be capitalized when using its proper taxonomic names, Cannabis sativa, Cannabis indica or Cannabis ruderalis.
No, it shouldn't be capitalized.
No, circa does not need to be capitalized.