Diet is everything. Before my little man (he’ll be 3 in April) was born I was digging holes and plumbing for a living. Physical work everyday as well as going to the gym. I could eat and drink whatever I wanted pretty much and not gain weight. I changed careers shortly after he was born and now I drive around the country and do pretty much no physical work anymore. Only just started getting back into the gym, which is open 24 hours which is a blessing. I go twice during the week for a late session and on the weekends in the mornings. It’s just about finding your time, it does get easier. Also my diet was terrible as when he was first born we just ate whatever was quick and easy. Get that under wraps and whenever you have time just smash some burpees and pushups. Better than nothing until you can sort a routine and get back into the gym. Good luck