about my study

Nowadays, g Global warming is an worldwide important issue worldwide.

(Ah, firstly, it looks like teachers often teach students to use "nowadays" in their essays. In my opinion, it is redundant, it looks out-of-date and it weakens your argument. Global warming will be an issue in the future as well, and we don't have to stress the present. So try to avoid "nowadays" in essays. Secondly, I put "worldwide" at the end as it feels more natural, for me.)

One of the causes of this global warming is considered to be a Greenhouse gas emissions.

("Global warming" is uncountable. You cannot use "this" to modify it. "G" in "Greenhouse" should be capital)

Greenhouse gases are released in the all throughout our lifetime by in diverse ways.

(There are more than one kind of Greenhouse gases.)

In other words, it is possible to reduce the greenhouse gas emissions (by device our life?).

(I don't understand what do you mean by "by device our life". You mean "by using more energy-efficient appliances?")

Then, we performed a simulation for the purpose of reduction of reducing Greenhouse gas, being conscious of bearing in mind the lifecycle of the entire Building 5 (by device our life?).

We tried to reduce Greenhouse gas emissions by changing all fluorescent lamps of type "FHF-32EX-N-HX" type with the to LED lamps of type "ES1200-SW" type . This type, "FHF-32EX-N-HX" is a fluorescent lamp that is used most often in Building 5. In addition, LED lamps does more less have lower power consumption than fluorescent lamp and LED lamps have longer lifespan is longer than fluorescent ones lamps lifespan. We take took the lamp’s all lifecycle of lamps into consideration, product to disposal, and we compared the power consumption before changing lamps to and after changing lamps. As a result, we can expection expect that a reduse reduction of Greenhouse gas emissions by ○○％.

have i some mistakes about made any mistakes in my english?