I think they can be helpful but sometimes aren't they might not be.

feels a little odd

The good thing is they make us feeling relaxed .¶

So it's easy to ask them some questions with a happy feelingout hesitation .

They may have wrong teaching skills and make us sad or embearreassed .

Family members can sometimes lose their patientce .

They can be sad or angry when we study slow or can'tunable to understand something quickly .

An essay: Learning things

Title case could also be used here, and using it might be more natural or preferred: "An Essay: Learning Things" or "An Essay on Learning Things" or "Learning Things" or "On Learning Things"

Some people think that family members are the best people to teach you how to do many things , such as cooking or driving.

I think they can be helpful but sometimes aren't .

People may say "but sometimes aren't" orally, but it seems a bit too "loose" for writing.

Something like these may be more typical:

I think they can be helpful sometimes.

I think they can be helpful, but not all the time.

The good thing is they make us feeling relaxed , so it's easy to ask them some questions with a happy feeling.

So it's easy to ask them some questions with a happy feeling .

"So" is a conjunction, so it should either be removed from this sentence or kept in when this sentence is attached to the previous one. If you don't want to add it to the other sentence, it could look like this:

That makes it easy to ask them some questions with a happy feeling.

Otherwise n the other hand, some family members are not good teachers .

"otherwise" isn't used this way, at least not that I have seen. Two examples with otherwise:

They had to submit the payment by 5pm or otherwise be charged extra.

She decided she would change the car's oil on her own. Otherwise, she would have to pay someone to do it for her.

You could also say "contrarily" or "however" before the comma for words that introduce a contrast.

They may have wrongbad teaching skills and make us sad or embearreassed .

"wrong" implies that they may have good skills, just not for a particular topic. If they are bad teachers, then saying they have bad/insufficient/inadequate skills is better. Also, I don't know why, but "embarrassed" has to have those two a's.

A professional teacher will teach the best way .

Family members can sometimes lose their patient ce.

I don't know if this always works, but words ending in "-nce" seem to be nouns. Patience, obedience, malfeasance, presence, ordinance, and ordnance are all nouns, for some examples.

They can be sad or angry when we study slow or can't understand something quickly .

In my opinion , learning from family members can be good, but in some other ways , it can make us feel worse than feel better .

"but" introduces an independent clause and thus needs to be preceded by a comma