There's a very inexpensive book called "English Grammar for Students of French." It might be useful for you to get a handle on some grammatical ideas that can be useful.
>it must have something to do with the existence of a direct object but I don't really know what that means
Yes. A direct object is basically something that is acted on, as opposed to the actor or subject doing the action. In "Jane threw the ball to Tom," Jane is the subject, the ball is the direct object, and Tom is the indirect object. (Close enough for now.) You might find it useful to get a book like "English grammar for learners of French."
Use the form ending in "que" when it's for the direct object; "qui" for the subject. So:
"Qui est-ce que tu vas aider a faire le ménage?" Who is it that you're going to help? Who are you going to help? You help them, just like you move a chair. They're a direct object of your helping, so it's "que" at the end.
"Qui est-ce qui va t'aider a faire le ménage?" Who is it that is going to help you? Who is going to help you? The person is the actor, the one doing it, the subject, so it's "qui" at the end. (And in fact you are the direct object in that one, the one being helped.)
>I understand present, past, future. Could anyone define the others?
There's a book that some people find useful, if their high school and college careers didn't include very formal looks at actual grammar as linguistics understands it. https://www.amazon.com/English-Grammar-Students-French-Learning/dp/0934034427
For the three that you do understand, I'd just add that of course French has multiple "past" forms (just as English does), in the indicative: le passé composé, l'imparfait, and the plus-que-parfait among others. And the future could be either futur simple or future proche (a bit like the difference in English between "she will do X" and "she is going to do X").
Otherwise:
Present conditional: This is like English "she WOULD do something" (typically connected with an "if" condition -- hence the name "conditional").
Subjunctive: Whether present or past, the subjunctive is typically used in subordinate clauses after a main clause has used certain verbs of obligation, desire, emotion, etc. In English, the subjunctive has almost disappeared, especially outside the U.S. Even in the U.S. it remains only for some speakers or regions. "She ordered that he BE taken away" versus *"She ordered that he IS|WAS taken away." Or "I wish I WERE in Monterey" versus *"I wish I AM in Monterey."
Gerund: French limits the actual label of "le gérondif" to uses in clauses that begin with "en" -- So "je pense EN marchant" to mean "I think WHILE I am walking." That -ant form participle (allant, marchant, travaillant, etc. for aller, marcher, travailler) is like the -ing form in English (goING, walkING, workING).
Imperative: Like with the word "imperious" -- it's required, an order or a command. Kids and parents are constantly using the imperative: Do this, don't do that, wash your hands, pick up your clothes, clean your room, take out the trash, put out the dog, bring in the cat ....
Infinitive: This is the dictionary headword form of a verb. In English, some people are taught that it's the "to" form: to walk, to work, to think, to type, to wash, etc. Of course the dictionary uses the "bare" form (leaving off the "to" marker). In French, it usually ends in -er, -re, -ir, etc,: parler, montrer, finir, dormir, rendre, plaire, etc.
Participle: Again, this can be in two forms, either the present participle -ant form that appears in gérondifs, or the past participle, which is used to form compound tenses as in "j'ai lavé la vaiselle" or "on a marché pendant trois heures," or "elle a fini son travail." In English, it's either the -ed form (worked) that's used in compound tenses like "they had worked on it" or it's the -ing form that's used to form the present progressive or near future like "they are working."
Edit: mis-spelled a word. Added last sentence for English beside French.
English-Grammar-Students-French-Learning is the best grammar book I think.
The best book I've found so far is English Grammar Students French Learning, it juxtaposes the two languages together to get a good grasp of what's going on.
Well, I should say that I learn best when I understand the grammar, both for comprehension and composition. It's like a logic puzzle for me. Plain immersion doesn't do it for me. There's a reason why French school children are drilled in written grammar - it's quite different from spoken. Moreover, I am a firm believer in learning hard core grammar to prepare for standardized language testing - it counts for about 30% of any test, at least. It's the middle section in the TCF.
So, I found french grammar books written for French students - it forces you to work completely in French and improves comprehension faster, I think. It also introduces you to French cultural stuff at the same time. Something like the Grammaire progressive du francais series.
I did lots of random online French website conjugation exercises. There are plenty of them, although they look like sites from 1998.
For listening, I used the TV5 Monde website mentioned above a lot for preparation, first with videos and then just the listening exercises. And then as I started to feel confident, I did their online timed tests. BTW they closely match the real TCF material because they provide the content for the test!
I watched French movies with French subtitles, not English. And I watched French news online - their accents are quite clear.
However, within 60 days of the test I generally listened to radio online, with transcripts if I could find them. Video news becomes a problem because you build a false sense of comprehension for testing. TCF listening tests are audio-only, no video.
Finally, when you get stuck on a grammar point, as I still do, I highly recommend either English Grammar for Students of French or Side-By-Side French and English Grammar.
Good luck!