Benim evim and evim are the same.

when they are same then why we use benim evim because by using benim evim we emphasize the house is mine

I am a beginner learner as well, but hopefully my comment will be helpful.

Turkish differs from English in that instead of using pronouns alone to express, for example, possession (my, your, his/her/its, our, your, their) in Turkish special endings (suffixes) follow the noun and are attached to it - they are "suffixed" at the end. So if you were to compare English to Turkish in terms of word structure it would look something like: my house (English structure) - housemy (Turkish structure) - so basically all you need to do is take the suffix that corresponds to each person and attach it to the end of the noun. So to say housemy, houseyour, househis, houseours, houseyour (pl) and housetheir - you´d attach suffixes to the word ev: evim, evin, evi, evimiz, eviniz, evlarý. In English you don´t attach any suffixes to the end of the noun so you have no way of knowing if the house is mine, yours or his - that´s why you HAVE to use pronouns (my, your, his, etc.) - in Turkish the kind of suffix you use tells you whose the house is, so you don´t have to use pronouns (benim, senin, etc.) - evim, evin, etc. is enough for the listener to know whose the house is. However sometime you want to emphasize it - in English you´d do it by emphasizing the word in your speach, for example: This is MY house. In Turkish you do that by also using a pronoun in addition to the suffix at the end: Benim evim.

If we think -in as the Saxon genitive in English:

Ben-im = I´s (like John´s)

Sen-in = You´s

O-nun = He´s

Biz-im (

Siz-in = You´s

Onlar-ýn = They´s

Same principle applies if you want to talk about what or how somebody is - only you would use suffixes for "to be" - so instead of saying I am beautiful, you´d suffix an appropriate ending to the end of the Turkish word for beautiful - in English it would look something like beautifulIam, beautifulyouare, beautifulheis, beautifulweare, beautifulyouare, and beautifultheyare (güzelim, güzelsin, güzel, güzeliz, güzelsiniz, güzeller).I like your way seeing them that way. Small correction actually they were something like as follows as separate words and all becoming suffixes over time:

beautiful-am-I, beautiful-are-you, beautiful-is-he, beautiful-are-we , beautiful-are-they

How to know which ending to use with which person? Well, that´s one of the things you just need to memorize

I am a beginner learner as well, but hopefully my comment will be helpful.

Turkish differs from English in that instead of using pronouns alone to express, for example, possession (my, your, his/her/its, our, your, their) in Turkish special endings (suffixes) follow the noun and are attached to it - they are "suffixed" at the end. So if you were to compare English to Turkish in terms of word structure it would look something like: my house (English structure) - housemy (Turkish structure) - so basically all you need to do is take the suffix that corresponds to each person and attach it to the end of the noun. So to say housemy, houseyour, househis, houseours, houseyour (pl) and housetheir - you´d attach suffixes to the word ev: evim, evin, evi, evimiz, eviniz, evlarý. In English you don´t attach any suffixes to the end of the noun so you have no way of knowing if the house is mine, yours or his - that´s why you HAVE to use pronouns (my, your, his, etc.) - in Turkish the kind of suffix you use tells you whose the house is, so you don´t have to use pronouns (benim, senin, etc.) - evim, evin, etc. is enough for the listener to know whose the house is. However sometime you want to emphasize it - in English you´d do it by emphasizing the word in your speach, for example:  This is MY house. In Turkish you do that by also using a pronoun in addition to the suffix at the end: Benim evim.

Same principle applies if you want to talk about what or how somebody is - only you would use suffixes for "to be" - so instead of saying I am beautiful, you´d suffix an appropriate ending to the end of the Turkish word for beautiful - in English it would look something like beautifulIam, beautifulyouare, beautifulheis, beautifulweare, beautifulyouare, and beautifultheyare (güzelim, güzelsin,  güzel, güzeliz, güzelsiniz, güzeller).

How to know which ending to use with which person? Well, that´s one of the things you just need to memorize