I assume that by 'ge' and 'de' you mean the characters 个 and 的 respectively. Of those two, only个 is actually a measure word, while 的 is a particle. You weren't very specific on the nature of the 'problems' or your level of proficiency, so you might get more 'help' than you've bargained for. But here we go:

Before we come to 个, a word or two on Chinese nouns in general. In general, Chinese nouns are like sugar, or more exactly, they are used similarly like the English nouns such as 'sugar', 'coffee', 'tee', 'information', or 'advice'. What these English nouns have in common is the fact that they CANNOT be used together with numbers or some articles without further ado. In standard, formal English can't say (X) 'one sugar', (X) 'two advices' or (X) "an information", but you can say: (OK) 'one LUMP of sugar', (OK) 'one PIECE of advice' or (OK) "a PIECE of information', etc. When used on their own such nouns (called either uncountable or mass nouns), do not specify exactly whether the speaker is talking of one or more things.

In Chinese ALL nouns act like mass/uncountable nouns. For example, 人can mean one person or many people, depending on the context. This applies virtually to any other noun you can think of. Sometimes, however, the context or the grammar might require you to be more specific. This is where the MEASUREWORDS come into play. What you practically say then is something like 一个人"one PIECE of person/people." or 一些人 'a few pieces of person/people'.

The grammar REQUIRES a measure word, when :

 1)      the noun is used with a numeral, i.e. when you want to explicitly state to how many things the noun refers to: 三个朋友 (three friends)，十个星期 (ten weeks)，五个小时 (five hours) etc.

2)      the noun is used with a demonstrative, i.e. when you explicitly say THIS (这) or THAT, (那) PREVIOUS (上) or NEXT (下) thing (this is quite logical, if you are pointing to an object/person it is clear how many we are talking about): 这个朋友 (this friend) 这个星期 (this week)， 这个小时 (this hour), but also 上个星期 (last week), 下个月 (next month)

3)      when 1) and 2) are used together: 这两个星期 (these two weeks / these last few weeks)

4)      the noun is used in questions with 几 (how many). In this case a measure word is obligatory: 你每天学习几个小时？(How many hours a day do you study?). 几 is used in questions, when the expected number is relatively small, i.e. not greater than 10 or a dozen, otherwise the word 多少 is used, which can be used both with or without the measure word: 你每天学习多少（个）小时？

 There are exceptions, however, as some nouns do not require a measure word, i.e. you say 三天 (three days).

As you see from the examples above, 个 is by far the most common measure word, and it can be used anytime. Most nouns, however, have very specific measure words. For example, 辆 is the common measure word for cars or bicycles, 张 for objects with a flat, horizontal surface, such as beds and tables, newspapers, sheets of paper or tickets, 本 for bound objects, such as books or magazines, There are no fixed rules, however. As an example, 只 is used for a number of small animals, such as cats, birds and rabbits; for dogs, however, 条 used to be the usual measure word (though 只 is nowadays often used instead). For fish and dragons, however, 条 still remains the only option. For larger animals the likes of a bull or a bear, go for 头, and so on. As you can see the measure words that go with a noun need to be learned with it together. 个 (ge) can, however, be used in most cases as a makeshift replacement for any measure word, especially in a casual conversation.

Not for 的. It can be used:

1)      after a noun

2)      after an adjective

3)      a gerund (verb+ing)

4)      after a clause

to convert these into an attribute. An attribute is a word that describes another word (usually a noun). Consider the following English examples:

1) MOTHER'S sister (noun)

2) a BEAUTIFUL girl (adjective)

3) a WORKING student / a student working at home

4) the man WHO LIVES NEXT DOOR. (clause) alternatively: The man NEXT DOOR (noun)

As you see, in English the attribute can appear in many guises, either before or after the word it describes. In Chinese, however, the attribute appears ALWAYS BEFORE the word it describes,  no matter how long it is, and the particle的 is used to attach it to this word:

1)      我的电脑 (my computer)

2)      漂亮的女孩 (beautiful girl)

3)      打工的学生 (working student)

4)      跟我一起学习的朋友 (a friend who's learning together with me)

The rules of using 的 are fairly simple. It:

1)      is always used with nouns as attributes

2)      is usually required with polysyllabic adjectives as attributes (monosyllabic attributes do not require的 as a rule, e.g. 好朋友 vs. 很好的朋友

3)      is always used with verbs and clauses

4)      almost always used with personal pronoun 我、你、您、她、他、它、and their plural forms, 我们、他们、他们、她们、它们 (note, that there is no plural form of 您 with 们; one would rather use 几位) to form possessives (我的 My/mine, 你的 your/yours, etc.). In some rare cases it can be dropped, e.g. with nouns denoting family members, teachers, parts of the body, organizations or institutions one works or learns at, etc: 我（的）妈妈、我（的）手、你们（的）大学、您公司