There are some ways to use a Soroban or an Abacus to learn arithmetic, the most popular one is the one suggested by Japan Soroban Committee. You may search for it on google.
With a Soroban or an Abacus, you can train your mental maths, mental arithmetic and be good at basic math soon.
Nowadays, people prefer the Japanese soroban to the chinese abacus as the Japanese one is easier to use and simpler in the structure. You can easily find abacus online courses in English. You can also find some abacus software on the internet.
With a Soroban or an Abacus, you can design some math games or mathematical games for your child to play. They are much better to your children than computer games.
Try to find an abacus software or a soroban software to buy or download and then use it to learn how to calculate on soroban or abacus.
If you cannot order an abacus software due to geographical distances, you can buy some abacus books which are available in your country.
Abacus software and abacus books are not very cheap at this time, but they are also not so expensive that you cannot afford.
I myself prefer an abacus software to an abacus book because the software shows good images or even videos that I can follow to learn step by step.