For learning grammar, all you need to do is learn through my Irish Grammar (lessons) thread. That's all you need to do for that!
For other tips of Irish please check out my thread HL Tips from Sryan Bruen.
Grammar is a very broad topic in irish, it applies to most things. Stuff like Reamhfhocail ,past tense, present tense, future tense.. If you want example you can look into the exam papers there's a dedicated part just for grammadach
grammar , well there is quite a lot to learn for example masculine and feminine nouns, how to change them when following 'an' , the genitive case, an módh coinealach (conditional tense), prepositions, past tense, present tense, future tense etc.