Very basic stuff

[The 10th Plague]

Hello,

I'm only just self-learning Japanese, and I would like to know if the following very basic dialogue is correct:

Person A:始めまして。私わサンデル*です。オランダのです。1 7年です。そらわチム*さんです。
Person B: 始めまして。貴方たちともだちですか？
Person A: そうですね。貴方ですか？
Person B: 私が「うちはさすけ」です。ときょに住んでいます。チ ムくん、貴方
の年なんですか？
Person C (チム): 私わ18年です。

*: I don't know if my name, Sander, would be transliterated like that.
** I also don't know if a friend of my, Tim, would be transliterated like that.

[nice gaijin]

はじめまして、私は(the particle "wa" is written は）サンダー(this is a closer transliteration in my opinion)です。１７歳です (sai, written either as 歳 or 才, is used for age)。この方(this person)はティムさんです。

はじめまして、友達ですか。 (I prefer to avoid using "you" in Japanese as much as possible, and I don't think it's necessary in this case. Also, the question mark is not necessary, as the か particle denotes a question)

I'm not sure what you are saying in the third part. "yes we're friends. and you?" as in, you're asking for their introduction?

私はウチハサスケです。東京（とうきょう）に住んでいます。ティムさん(introduced as san, chances are you would continue to use that)は何歳ですか(何歳 or いくつですか are used to ask how old someone is)。

１８歳です。 (since he's responding to a question and it's obvious that he's talking about himself, 私は can be omitted.)

[Elizabeth]

はじめまして、私は(the particle "wa" is written は）サンダー(this is a closer transliteration in my opinion)です。１７歳です (sai, written either as 歳 or 才, is used for age)。この方(this person)はティムさんです。

はじめまして、友達ですか。 (I prefer to avoid using "you" in Japanese as much as possible, and I don't think it's necessary in this case. Also, the question mark is not necessary, as the か particle denotes a question)

I'm not sure what you are saying in the third part. "yes we're friends. and you?" as in, you're asking for their introduction?

私はウチハサスケです。東京（とうきょう）に住んでいます。ティムさん(introduced as san, chances are you would continue to use that)は何歳ですか(何歳 or いくつですか are used to ask how old someone is)。

１８歳です。 (since he's responding to a question and it's obvious that he's talking about himself, 私は can be omitted.)
When giving your age it is really unnecessary to repeat 歳。１７です、１８です is fine. Leaving it in would be like answering "I'm XX years old" to the question in English instead of the normal XX.

[The 10th Plague]

ありがとう。 わかりました。 ;) ^^