I started with Red Sea blue bucket myself, so I think it's a solid place to start. You can also get Instant Ocean Purple Box and save a bit if cash too.
Once you pack your tank with corals then maybe consider moving to Red Sea Coral pro (black bucket) Instant Ocean Reef Crystals or any other similar brand.
Those products are geared towards folks that have smaller setups that need higher than normal levels to avoid using supplementation.
As others have said any salt will work, but given you have no corals and it will be a long time before you add enough coral that consume a meaningful amount of elements, just get whatever is cheapest and available.
Blue Bucket FROM Red Sea mixes clean and quickly, has a nice bucket you can use for other chores so I'd go with that.