iATKOS | United Kingdom

I just picked up a Lenovo Thinkcentre E73 with the intention of installing OSX Catilina for my first Hackintosh. I've been doing quite a bit of research on it and have decided to go with OpenCore installation. I was wondering what would be the best/cheapest PCI-E Wifi/Bluetooth card to go with? ethernet is available but I would like the airdrop experience. Also, the E73 currently has the I3-4150 installed, is it possible to upgrade this to i5 or i7 after the installation or should I do it before? does anyone have any good suggestions for guides or videos to recommend? I've been watching technolli and reading the opencore guide, wondering if there's anything else I should be looking at. Thanks!