Unfortunately, there is no easy answer for you. You just need to start. If you are a stay at home mome and have 3 weeks to do this, you should set goals for each day and try your best to stick to them. If you break it down per day, at least you know what needs to be accomplished each day. See if a friend or two can help you. Truly ask yourself if you need the items, or if they are just taking up space. If not, you have to let it go. You can donated it, discard it or whatever you need to to help satisfy yourself. If you can afford it, hire help as I am sure you can't do a lot being 8 months pregnant.

im 8 months prenant with 4 kids already and i got about three weeks to do my home it has built up for four years now and i dont know where to start and im all alone recently i have gotten another apartment upstairs from mine and have made three bedrooms so far but now all the mess is built up on my second floor where we have been living im keeping both apartments so i have enough room for my children but now im stuck with this mess and all alone to do it and not much time to do it and i need advice on where to start plus i need to go through alot of stuff because it is mixed all up no one will help me please can someone give me some advice on what to do or where to start to make some big changes quick