Whether it can give me a good profit.?? .

It will depend on the campaign's pay rate you're participating mostly the more followers you have the more you get profit on it.

I have a twitter that I think qualify.

As long as you have more bitcoin or crypto related followers, then it's enough.

And then how long usually I'll get bitcoin as they promised..?? ,

Most Twitter campaigns pay weekly.

Will I always get a twitter campaign is in it.?. Thanks for the help to help me in answering all the questions that I ask

It will depend on also if how fast you reply to the campaign if you want to apply, as it has first come first serve rule for accepting participants.