Hello Joy,
Thank you for the beautiful question.
First In, First Out, commonly known as FIFO, is a valuation method in which assets produced or acquired first are sold, used, or disposed of first. In other words, First In, First Out (FIFO) is an accounting method in which assets purchased or acquired first are disposed of first.
Let me give you a typical economic scenario- Say with the persistent rise in prices of goods (inflation).
Example 1: if FIFO assigns the oldest costs to the cost of goods sold, these oldest costs will theoretically be priced lower than the most recent inventory purchased at current inflated prices.
Example 2: Imagine if a company purchased 100 items for N10 each, then later purchased 100 more items for N15 each. Then, the company sold 60 items. Under the FIFO method, the cost of goods sold for each of the 60 items is N10/unit because the first goods purchased are the first goods sold. Of the 140 remaining items in inventory, the value of 40 items is N10/unit and the value of 100 items is $15/unit. This is because inventory is assigned the most recent cost under the FIFO method.

https://www.freshbooks.com/hub/accounting/calculate-fifo-and-lifo

https://www.bing.com/videos/search?q=fifo+method+accounting&&view=detail&mid=38EB67F8F1FD3073395338EB67F8F1FD30733953&&FORM=VRDGAR&ru=%2Fvideos%2Fsearch%3Fq%3Dfifo%2Bmethod%2Baccounting%26FORM%3DHDRSC4
https://www.bing.com/videos/search?&q=fifo+method+accounting&view=detail&mid=6A4256ED17F6B15BBCCD6A4256ED17F6B15BBCCD&FORM=VDRVRV&ru=%2Fvideos%2Fsearch%3Fq%3Dfifo%2Bmethod%2Baccounting%26FORM%3DHDRSC4&ajaxhist=0

You can use the links above to learn more about FIFO and LIFO….
Try creating various practical FIFO scenarios on Peachtree and remember I am always open to further questions and areas of confusion.

Thank you again for the question.

And (To all) please feel free to discuss what you’ve learnt even if its outside the scope of these lessons, feel free to refer books and other helpful materials on topics you’ve learnt.

Thanks