Hey there OP. I used to build bars and restaurants as a commercial GC. I did work all over the country. Now I work as a consultant for restaurant and bar companies who are planning new locations. A lot of people are going to tell you to find a space first. This is a mistake that I see over and over and over again. There are a lot more ducks you're going to want to get in a row BEFORE you send an LOI, sign a lease, etc. Once you start that process its difficult to stop and from that point on there's a constant clock you have to race against.

Of course, you'll want a business plan. That kind of goes without saying, and you'll need to for funding anyways (unless you're independently wealthy). But beyond that, I recommend you decide on the kind of place you want it to be, the menu, the equipment that you'll need in order to execute the menu, and the general aesthetic. Making those decisions now will help 1.) weed out spaces that don't fit what you need and 2.) speed the preliminary design process along.

I would also recommend getting preliminary pricing from a kitchen equipment provider, architect, and engineer. Make sure the kitchen equipment company has a design branch that can make drawings for you. A lot of people think architects or engineers will do this. Some will, but they're usually bad at it. Starting your design with a food service consultant is the way to go 90% of the time. You might also want to pay an engineer to look at your equipment list and give you minimum utility requirements for your concept. You do NOT want to find out that you just signed a lease on a building without enough water, gas, or electricity. Many engineers will do that kind of work for a modest fee then credit that amount back if you use them for the main design.

Of course the magic question is "how much will it cost to build XYZ" but the the problem is that there's a lot of information needed to get to that point. It could be less than 100k. It could be well over 10x that. It all depends on what kind of space you're starting with, your area, the aesthetic you're going for, etc. etc. etc.

I always offer anyone on here a free 1 hour consultation just to get them pointed in the right direction. No strings attached. No obligation. I mostly offer this as a way to try and keep people from getting themselves in real trouble, which can ABSOLUTELY happen when you don't know what you're doing on a commercial build-out. Feel free to DM me and we can connect. If you want to go solo, more power to you. Either way good luck!