honest answer?
you're international, so the changes of you getting a job as a founding engineer at a "good" startup are low.
1. you're looking at 1% equity with cliff.
2. consider that 90% of startups fail, and 90% of startup founders are scammers/scumbags. i have friends who have been screwed over by such people.
3. as a founding engineer, you'll be doing a TON of work, and they might just fire you after 6-8 months when they have something built they can use to raise more money. leaving you with nothing and hopefully they at least paid your monthly salary (unless you get duped by "vision" and don't take pay because again - you're international)
my suggestion - either do your own startup in your own country
OR
apply to a stellar unicorn startup that's now raising series B at whatever level you can get in. aka a non-shit, validated startup that has an actual chance at IPO or strong acquisition. you might make 10-25x on your options as an employee.
as for your self-marketing, you just need to go on LinkedIn and start messaging people or find interesting founders, go to their websites, and send them an email. worst case they don't respond, who cares?