بسم الله الرحمن الرحيم
الحمد لله رب العالمين
The word 'الحمد ' is a noun. How do we know it is a noun? It is prefixed with the definite article 'ال'. This is the first sign of a noun that we have learnt . (Note: there are different types of ال with different functions.)
The word حمد means praise, when this type of ال is added then it gives the meaning of all encompassing. So الحمد means All praise.
Now usually when ال is added it turns a generic word to definite. For example, بَيْتٌ means a house (generic), but when you add ال it becomes اَلْبَيْتُ which means 'the house' (definite).
So remember when you see ال prefixed to a word then that shows two things, one that the word it is attached to, must be a noun; and two that the word has become definite.
Hope that was beneficial. May Allah reward you and I both.