You ferry for your car from Bali to Lombok. From Padang Bai , and there are ferry trips further on.
Have got an extended visa, most are only 30 days then you have to leave country ( usually to KL or SingaporE) and then re- enter.
Lots of places to stay but you are in the middle of the season, hunting for accommodation on the ground will be challenging !
Indonesia for the first time is an exciting and chaotic. Get a book by Peter Neely " Indo Lingo" it has lots of places to stay, coupons for cheaper stuff, and some basic Bahasa Indonesian ( Language ) conversation skills and polite manner of address. It covers all the different islands you are planning to visit!
The recommended site from Big H is a good way to go too , use them and the book.
Indonesia's motto is " unity in diversity " and diversity rules, underlying the world's largest Muslim nation, Bali is natively Hindu, Lombok is both , Nias is shamanistic animists, Some of the Mentawais are Christian as is parts of Flores and Timor.,
Have travel insurance, a serious illness or accident will bankrupt you if you don't have it.
Most surf camps require a sighting of your insurance policy!
The book has links to reputable insurance and if you could get it before you go, good stuff.
How is your surfing ability? There is everything from death slabs to gentleman's long board waves.
One more thing , Indonesia is most likely very different from where you come from ( where is that BTW?) and you need to just relax and smile,. Take it easy!
Learn what "tidak apa apa " means and life by it gently,.

Have fun enjoy thoroughly
I've taken up troll hunting just for fun, instead of a rifle I'll just use a pun! 冲浪爷爷