Hola Michael,, el presente perfecto es un tiempo gramatical del inglés y se usa para hablar de cosas que empiezan en el pasado y se siguen dando en el presente. También se usa para acciones que se consideran repetitivas y por último para aquellas que acaban de terminar. El past perfecto (have /had + past participle), se usa para describir una acción remota, anterior;....es decir de dos acciones pasadas, una sucedió antes que la otra y para diferenciarlo uso el pasado perfecto, por ejemplo:I've just set the table /I had set the table when Peter arrived home for dinner.

Research the topic chosen; write essential information to be included. Organize the information in paragraphs: introduction (global idea), a couple of paragraphs that support the main ideas, and finally write a conclusion. Don't forget to check your spelling!

You should have an interview and afterwards, take a placement test. Depending on the results you will be assigned a level from the CEFR

First of all you should have an interview, and then take a placement test in order to know your level of English according to the CEFR

To have lunch. As you say ..have breakfast or have dinner. Let's have our lunch before the class. I eat lunch after 1.00 pm