Questions & Answers about Этот цвет подходит к твоей новой рубашке.
Because цвет is a masculine singular noun. The demonstrative этот must agree with the noun in gender, number, and case.
In the nominative singular:
- masculine: этот
- feminine: эта
- neuter: это
So этот цвет is the correct form for this color.
Подходит is the 3rd person singular present-tense form of подходить.
It is singular because the subject is цвет, which is singular. So literally it is something like:
- цвет подходит = the color suits / matches / goes with
Russian present tense often covers meanings that English expresses with goes with, matches, or suits.