1. Yes, of course you can. Not every user is comfortable for calls

especially if we're not paying them money directly. Google forms should be good enough. Make sure to design good questions and answers inclusive of all communities ( e.g. the question is "What's your gender?" so give more options than just "male/female"; at least option to skip); you can't also change or rearrange the question in the moment as we can do on direct conversation so yeah ask better questions.
2. My usual UX workflows can be described as ( I don't do much UX nowadays, in freelance web dev work mostly; it might not be "industry best practice though"

):-
start with research ( create 2-3 personas -> some journey maps; i don't do any empathy etc maps unless i have good amount of data and time -> get a sense of copy/content client is gonna fill in website )
after than i create a sitemap ( or "information architecture" as people call it

) and rough golden user flow with the info i have available from client, content and journey maps.
then i get to wireframes ( i really like google's '8 Crazy minutes' technique in early phase. )