I need advice about using Affiliate Marketing

Hello, in the past, I had a website where all the products were affiliate links and I used to earn from it. (This was just a little sideline business to my main work at the time, but it did make quite good passive income using Amazon and a few other affiliate programmes). I had a friend who uses to do our SEO for free plus I got some PR on it myself which helped to draw traffic.

I would like to get back into this, as with over 25 years experience in Retail I have the ability to curate collections of bestselling products and know what will sell well.

I need advice as to how I do this best and at as little investment as possible. A website? Shopify? Pinterest? Instagram? Which is easiest? I would like to just stick with Amazon at this stage. I have a theme/niche that I would like to specialise in which I will keep private. But if you could give me some advice, or if indeed there is anyone who could help set this up for me and shoe me how and where to drop links etc. I'm very rusty on this- I have the "selecting products and branding capabilities" but not the tech side of things. Obviously if you can and are chosen to help me to set up, I will book that as another job, this first one is just to discuss.

Ps. You see many Instagram posts regarding "side-hustles" for busy Mums, where they are simply working with affiliate links to generate income. Do these really work? Like I say, this is just a side hustle to my normal work just because I know that I have a skill that I may aswell put to use, plus I really enjoy it and it generated income in the past. I realise the landscape has changed however, so how can I still do this, whilst moving with the times to make it a success?

Thank you
Joanne