When we say 10年"も住んでいる" instead of 10年住んでいる, to emphasize ''how long'' have you been living, however it dose not exactly mean that Mohammed says "more than". More than we would say 10年以上. 住んでいる is present perfect continuous tense which is "has been living". 住む is Infinitive. I hope this makes sense :)

Hi! If (も) appears after counted nouns, periods and quantities, it's generally used for emphasis. In this case (10年も), it emphasizes the period. Note that in other cases, も after numbers can also mean (more than). 住んでいる indicates a continuous action. First you have the verb 住む, you turn it into its (-te form) --> 住んで and add いる --> 住んでいる. If you haven't learned such a verb form yet, then all you need to know for now is that this is what it means. In our sentence it literally means "has been living".

10年も means more than 10 years. and ~ている refer to present continues form. good luck!

10年も　means " as long as 10 years " . FOR is 間(かん). So , we can say 10年間も住んでいる。Your sentence omits 間. It is quite common in speaking. 住んでいる　has 2meanings in English. One is I have lived. For example, 1年間、東京に住んでいます。 The other is live in now. 東京に住んでいる友達がいます。　I have a friend who lives in Tokyo.