Congratulations. Good job making a plan and having the courage to own it. You have started on a path that only good can come from. Stick with it, take chances, everything can't be a winner, but when you get it right, you will notice results that you will like. When you catch an attractive woman stealing a look at your shoes, or when people look you up and down then give the unconcious nod of approval you'll know you got it right.
Brooks Brothers Advantage Chino Pant are great quality, catch them on sale or better to get a new with tags someone else paid the retail on. I don't have any Chelsea boots, but the Thursday Boot Company boots are so sweet. I have the Cap toe boots ( Captains ) in Black and Brown. Paid retail on Amazon for one pair, got the other on ebay for 50 bucks in like new condition. All white sneakers are on offer from all the sneaker makers. Adidas shell toe's are pretty timeless.
1) Always be fuckable
2) Fit is the single most important attribute
3) Get value for your money pay for quality material and finishing
4) Attention to detail
5) Continue to improve yourself
For your fashion end state, how do you want to present yourself. My answer is to have a put together, clean, appearance with clothes that flatter you. Rule number 1 " Always be fuckable " in your appearance and in the way you carry yourself. Whether you are dressing casual or dressing business. Wear clean clothes with good quality fabrics that smell good with colors that have depth, no stains, no dirt, no snags, Clean shoes, Clean haircut, smell good not overpowering or bad, wear a good looking high quality belt that complements the shoes and a watch that goes with both.
Fit is rule number 2. You need to know your Chest, Neck, Sleeve, Waist, and Inseam measurements so that you can buy clothes that will fit regardless of the manufacturer. You tube videos and instructional web sites for how to measure are good sources for the how to part of taking measurements. I like lots of different fit's from fitted suits to loose fit hoodies and joggers to compression and under armour clothes for workouts. What matters is the fit should flatter your body and be complementary not clashing.
Value is rule number 3. You pay for the name but you should be paying for the quality. You can shop brick and mortar thrift stores, auction web sites like ebay and poshmark for NWT or new with tags clothing that is fractions of MSRP. Find local sources that you can get good value from.
Attention to detail is rule number 4. For example Shoelaces should be high quality not dirty or dingy. Shoes should be dirt free, clean and look good. Women pay attention to your shoes. They make judgements about how you take care of yourself based on how you take care of your shoes. There is no end to attention to details ie; Knot types on neck ties and knot type on shoe laces. Learn shoe cleaning / polishing techniques, colors, mirror shines, edge dressing. If you have good quality shoes, they should last forever. I had some 8 year old Red Wing Engineer Boots re soled for 80 bucks just recently and took them on a camping trip. Awesome. They looked killer.
5. Continue to evolve. Take a selfie in a full body mirror daily so that you can see what works and why over time.
Some of the things I try to do are to read red pill on Reddit. Watch Alpha Male video's on you tube, recently I've been watching Kirby Allison videos on you tube from the hanger project. There is so much to work with I'm still working on learning the color wheel, how to match colors and learn about what is complementary and what is clashing.
Try some different shoes and boots to see what you like. I love Allen Edmond's mens shoes, Thursday Boot Company Boots, Under Armour sneakers, Red Wing Boots, Tim's. Best of luck to you on this journey.