Needing some good advice

Brenda
Sorry this is a really long story but I need some advice. 
2 years ago I fell pregnant with a man I thought was "The One". But unfortunately I miscarried with that pregnancy due to circumstances with that guy. So I moved to a different country because he played too much mind games for me to handle. A year went by and I was actually miserable for once in my life because I felt alone. Eventually I moved back to my own country after been seperated from my ex. 
Months went by and my cousin and his partner invited me to their house unbeknown that they had a friend who was single. It took them a few weeks to hook us up because we're both shy people. Finally we ended up hooking ourselves up through fb and it took me to have the balls to ask him. Now my partner and I have only been together for nearly 7 months. Honestly my family was envious of our relationship at the start because of how great we get along with each other but they love us been together. 
He is much older than me by 15 years and has 4 older children with his previous girlfriend. 3 live with him under his roof. 2 boys 16 & 13 and 1 girl 10. Recently I found out I was pregnant and I told him. I actually gave him options if we wanted to keep or what? He said yes we should definitely keep the baby. Now he knows we're having a baby we don't kiss or cuddle like we used to. It makes me wonder if its worth staying in this relationship
His kids are starting to get on my nerves because I can cook and prepare something that takes me an hourof constant standing. My only expectations from them is to only do the dishes but its hard for them to get off their ps3 & ps4 games for 15 minutes to tidy up. 
I hate the fact my partners parenting skills isn't sharp because his kids don't need to do anything. They're teenagers still in school but they can sit on the games for more than 16 hours a day in the weekends and over 8 hours a day during weekdays which I know is way too long. 
My partner hates the fact that I moan about his kids but it's frustrating for me because they don't need to to do basic household chores. I pretty much have to moan for him to help me do them all or else the house is constantly dirty and thats just not me. 
This is just a hard situation for him because those are his children and he should have to protect them. But what is he teaching them?? He needs to be a parent not a friend to them. I've even suggested that the oldest should find him a job for the amount of time he's on the game. I pay for all the food his kids eat. I got taught young how to be clean, like shower without been told. His kids have to be reminded to have one especially his daughter. 
Now I am having doubts with my partner about playing the father figure in my baby's life. I don't want my baby growing up not knowing how to cook for himself and be clean. I am constantly tired, phyically and mentally drained out everyday. My space away is when I'm working but I pretend to be happy when I'm not. 
I want to cry and move back to the other country so I am able to bring my baby up a better way than the way he has with his kids. 😭😭😭 its a really hard decision he's going to lose me and my baby soon. And I'm his very first girlfriend that isn't psycho on him.  Help please