I have been trying different wines rececipies. Don't know much, but its fun. If you taste the wine before bottling, say after 3 months or more and you don't like the taste, what can you do to adjust the taste or should you?

There may be a few basic things that you can change.
Acid too high or too low. Wine tannin will also change flavor. You can blend to change flavor or even lower the alcohol content of your wine. If your wine is too dry for your taste you can change it.

When do I start working on what I want in the wine? Although I check acid before I start fermentation I only want the acid with a basic range. Maybe .55 to .90%. After the wine has fermented for 3 months (approx) I start getting serious about setting the exact acid level I want. I wait until just before I am ready to bottle before I do any back sweetening. If you do back sweeten be sure to add 1 crushed campden per gallon and 1/2 teaspoon of potassium sorbate per gallon. Both at the same time. This will prevent re-fermentation. I like to use the white grape juice for back sweetening, or even topping off. Other times I will just use water. Especially if my alcohol is a little high.

I oak many of my wines. If you do too much before you put it on oak it will change anyway. Oak has some tannins in it. My wines are usually about 8 months from start to bottling.

It takes patience and time. Take lots of notes to refer to later.