Please capitalize where necessary: push your arms upward till you feel a good stretching of your chest and shoulders.
A: Push your arms upward till you feel a good stretching of your chest and shoulders.

Q: el cielo national park is the protected part of the ecoregion known as veracruz moist forests. it is located in southern tamaulipas, mexico in a tropical broadleaf forest.

A: El Cielo National Park is the protected part of the ecoregion known as Veracruz moist forests. It is located in southern Tamaulipas, Mexico in a tropical broadleaf forest.

Q: one of the most annoying things on the web are interactive elements, usually videos but also advertisement, that play sound automatically when a website is opened.
A: One of the most annoying things on the Web are interactive elements, usually videos but also advertisement, that play sound automatically when a website is opened.

Problem: 2. please select between airport/port depending on how you arrive to the country for your transfer.
Can you repeat this sentence, but capitalize it?
Answer: 2. Please select between Airport/Port depending on how you arrive to the country for your transfer.

Text: the idea developed, and i started selecting songs from over the years, starting with the javelins (in 1962).

Correct capitalization: The idea developed, and I started selecting songs from over the years, starting with The Javelins (in 1962).

Problem: the 1919 versailles diktat for it was not really a treaty was so harsh and dishonourable for the defeated nation that the american senate refused to recognise or adopt it (november 20, 1919); thenceforth, little by little, it was discredited.
Can you repeat this sentence, but capitalize it?
Answer:
The 1919 Versailles Diktat for it was not really a treaty was so harsh and dishonourable for the defeated nation that the American senate refused to recognise or adopt it (November 20, 1919); thenceforth, little by little, it was discredited.