advice buying chess board

There is a sub forum here specifically for chess equipment. There are many people there who can provide very good advice.
Here are the Official Standards
2.3 The height of the pieces, in descending height order, is as follows: King – 9.5 cm, Queen – 8.5 cm, Bishop – 7 cm, Knight – 6 cm, Rook – 5.5 cm and Pawn – 5 cm. These dimensions may differ by up to 10%, but the pieces must remain in descending height order.
2.4 The diameter of a piece's base should measure 40-50% of its height.
3.3 The side of the square should measure 5-6 cm. Four pawns should fit on one square.

There is a sub forum here specifically for chess equipment. There are many people there who can provide very good advice.
Chess Books & Equipment - Chess.com