twinvalleytech

@twinvalleytechdear friend if you are just starting with FPGA development I can suggest to use a simple and cheaper Cmod A7-35t development board. If you like to practice with a softcore MicroBlaze and interact with the fabric logic inside the FPGA, coding with VHDL/Verilog this board is very interesting and give an useful starting point. There are plenty of good tutorial around here and when get some feeling you can step toward to a more complex board.
Basys 3 (I've never used it) have a slightly higher cost, but more peripheral around the FPGA and then you can avoid to breadboard around the Cmod A7-35t but is up to you. Actually I've start to use the Cmod A7-35t, is very small and lightweight and a very good to start with basic IP Block Design, MicroBlaze testing, RTL with VHDL/Verilog coding, for my little experience a great board.
Bye

In terms of going for the SoC board, that depends if you will have a use for a dedicated ARM hard core processor. Will you have applications that will make use of it or are you solely focused on FPGA development?
If you only care about FPGA development and want to go between the Basys 3 or Nexus A7 along side that book I recommended, honestly, as the saying goes "buy cheap, buy twice". The Basys 3 is a fantastic board, but the Nexus A7 can do everything the Basys 3 can do and more. The Nexus A7 has RAM and an Ethernet Port that the Basys 3 does not and that is where the book calls up the use of the Arty A7. However the Nexus A7 also has the 7-segment displays that the Basys 3 has that the Arty A7 does not.
So if you decide to get that book and read it cover to cover, then the Nexus A7 should be a "1-stop shop" board that you can use throughout the entire thing. However it is worth noting that the Arty A7 board is only really required for later chapter, the Basys 3 can do everything needed for most of it.
When following the book you just have to be aware that if you are using the Nexus A7 the constraint files and setting up of the board in Vivado will be different, but as long as you are somewhat familiar / savvy with these already from your previous experience of FPGA's that should not be an issue.

This book is a great start. It begins with what logic gates are and builds upon that. From a basic LED being turned on and off with a switch all the way to implementing a soft core CPU on an FPGA and beyond.
The book is to be used along side the Basys 3 or Arty A7 dev boards, but honestly, I would opt for the Basys 3 for this book as most of the early chapters are geared towards that board more so than the Arty A7.
Everything taught in here is transferable to all other FPGA's. The book covers both Verilog and VHDL simultaneously, but I would only chose to learn 1 language first and skip everything related to the 2nd language for now, you can always go back and learn it later. It is however slightly geared more towards Verilog than VHDL, but all examples and exercises are shown in both languages.
https://www.amazon.co.uk/Digital-System-Design-FPGA-Implementation/dp/1259837904

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