Do you have a pic?

Typically white front doors are difficult to keep looking white. But they certainly exist.

Pic:

Sorry I should have been more clear-- is this an interior door? A front door? What does the rest of the space look like-- is it modern, MCM, some kind of historic era, 1980s?

You can certainly paint interior doors but most of the time its easier to get a new one unless the door itself is special (solid wood, original to the house, etc.) This looks like it might be a laminate? Veneer? That would make it a bit more difficult to paint.

Thanks for your answer. I am not sure about the kind. I am a first time home buyer😐. And yes the house is old 1969 built. Trying to give it modern look.

My guess is that it is laminate-- that was popular in the 60s thru 80s and the plastic door frame is a give away. This material is very difficult to paint-- note the shine-- that needs to be sanded so that paint will stick, even with a primer. And that is often not worth doing on what is essentially a plastic door. Your paint will peel with use.

Once long ago we painted some faux wood paneling in a basement. Used the best primer etc but it lasted less than a year. Paint just doesn't like to stick to these surfaces. You probably just need some new doors.

Thanks.
Will think about new doors then.

Do I need to change door trim along with the doors??

Hard to say without seeing the whole thing. My guess is yes. Unless you like the plastic.

If this is a mid century house and it has original features you might consider working with them instead of ripping them out. A lot of people really like that style. But if its 1980s and needs a refresh go for it.