i if want to start small project (site)
how much i need for basic one ? OR complex one ?
what is your small project? do you want to make ico? if you want to make ico, then you need big budget like more than 100 btc to start because you need to prepare many things but i don't know what should be prepare to make an ico. but if you only want to create a site, i think you can buy domain name and the hosting which is $150-$200 for a year, buy template which cost $10-$100, build the site (you do by yourself or hire web design and the cost is $100-$500). but its only for the range and i don't know the details.
I have more Knowledge in apk apps so that i prefer to start with it
not have many skills in ICO can give me start reference ?
For ICO's, you need a stronger base and a promising idea to capitalize off of. I'd suggest taking a look at current ICO's that are being advertised here on bitcointalk. You'll notice that a lot of money goes into the planning, paying employees, and especially advertising. However, in the chance that an ICO is successful, they can definitely make a lot of money and create a working coin. Definitely keep track of the ICO's available here to learn a bit more about how they operate.