workout advice

so my husband and i have decided that we need to start working out and eating better but we arent exactly sure on the right way to do it... my main goals are to drop some weight (20 lbs) and to start getting my body prepared for pregnancy so that way im already in the habit and can continue working out during my pregnancy when we start trying, and my husbands goal is to keep the weight he lost off and overall eat better... we are starting off by doing nightly walks but are there any good workout apps that are free and dont require a subscription of any kind that we can use to create our own personal regimens and diets that you would recommend?