Wow, there's an open ended question! You may find the fastest way to get started is to do some research on this forum for prior posts, as there is a HUGE body of knowledge here.

My favorite place to start is:
Please help with ventilation.
This is a "vintage" post with some incredibly useful basics. In particular, see kaseki's post on July 31st, which reviews the basics. Then lots of highly opinionated views on everything involved in getting good ventilation.

Easy Peasy Ventilation
Recent post resurrecting the ongoing religious debate over Vent a Hood.

Vent hoods and noise
Discussion of noise levels with vent a hoods.

If you review these you'll have an understanding of ventilation which already will far exceed what your average appliance salesman has. Then you can post specific questions and get inundated with advice here.

PS: one thing confusing on your post: are you saying you have not decided whether to put your range against the wall or on a central island? If that's the case, from a ventilation standpoint it's a no-brainer: wall mount hood will far outperform island hood, all other things being equal.

I am new at this and it shows! And yes, I have not decided about where to place the Capital 48 inch . The reason being that it would take up about 50% of the ONLY wall space I have therefore cutting down on cabinets . That's the problem with big dreams in a small world! Thanks for putting me on track towards all the information I should have checked previously, and for helping me in the early training period.

The working assumption of some of us here is that you will want minimum cooking grease and odor into the household and sound levels that allow holding a conversation. This can lead to costs commensurate with the cost of the CC range. Typically, one can choose only two out of three of economy, aesthetics, and effectiveness, and a large, high output range will push one away from any hope of economy, even if an unaesthetic commercial hood were to be used.

Generally, the ramifications of different kitchen layouts are best considered early. Use of an island or peninsula range means a bigger and higher "powered" hood is needed. This will be visually obtrusive if large enough to be effective. (I chose this path for more wall cabinets, FWIW.) It is also possible to hang cabinets over islands and peninsulas and gain the back to back cabinet space at the cost of visual blockage.

kas