I was wondering how a person can really concentrate on Allah swt in salah? Like what should we think about in our minds. For me my mind wonders off but then I try to get it back to Allah swt. What is the solution to this?

These are two books I recommend you read to get this done properly

101 Ways to Concentrate in Prayer https://www.amazon.co.uk/dp/190811021X/ref=cm_sw_r_cp_api_glt_i_W86S0H73CYSPASMEZZ8N