Whether a potting soil, or any purchased soil, is any good depends on many factors as well as just what you buy. Some potting mixes are peat moss, bark fines, perlite or vermiculte with some kind of nutrients added while other bags of soil might actually be the mineral part of soil with organic matter added.
If you are to be growing things in containers, pots, then you would want a potting mix. If you will be growing things in raised beds you would probably want soil of some kind, but that means knowing what it is you want since the trems "topsoil" and "garden soil" are meaningless terms that can be used to describe anything.

Thanks for the reply.
right, it is the top soil that confused me, one landscaping company close to me sell top soil, which is just compost plus sand, I doubt that will work for my raised bed.

You could use what the Square Foot Gardening folks use, which is called Mel's Mix, after the author of All New Square Foot Gardening, Mel Bartholemew's method of soil less gardening.

You should do a search on Mel's mix or read the book.

However in a nut shell;
1/3 coarse vermiculite
1/3 peat or palm coir (better imho)
1/3 organic compost made of at least 5 sources of compost. Make sure that your compost is that and not filled with peat filler as you have to adjust the peat component if it is in the compost.

Other tweekages could be made but that is the recipe as originally given.

Check MM in the Square Foot Section of this forum.

Here is a link that might be useful: Square Foot Section

Mel's great.
I have sandy loam soil & I use coffee waste compost, grass clipping compost, leave mold composted & kitchen waste.
A little animal manure a few times.
I have not problems, well it is hard to pick the 6 feet tomatoes plants, but I have a ladder.

I like Mel's mix, but even better for my rainy climate was mixing in with my existing clay soil to provide a bit of stability & moisture holding. Daily watering wasn't my style and soil was just a bit too loose for trellises not attached to wood boxes. We've been growing in our current boxes for 3 years and permanent beds without wooden sides for more than that.

If you don't have boxes you probably won't want Mel's mix which is basically a container soil.

Lasagna gardens might work better for you, too. Layering up is amazingly easy. Garden sides aren't necessary. Some climates do well with sunken gardens instead of raised. Used coffee grounds are free as is hay sweepings from the feed store. Inquire about bagging up what they sweep up after it spills when loading customer orders. I wear a mask, gloves, coveralls, & clean up after myself. Whatever the mix of hay & shavings is present always blends well as bottom layers of lasagna gardens we've built. Those gardens are loose & rich soils as compared to the "dirt" gardens.

Amend as jolj suggested & your soil will be productive.

You can build a Lasagna bed and not concern yourself about something called "topsoil". You could spend a ton of money and mix together something called Mels Mix. Or you coud simply add a lot of organic matter, for many of us this is free, to the soil you do have and make it better, somethign the other two processes will eventually do anyway.

Here is a link that might be useful: Lasagna Gardening 101