In late April or early May use the online system to get a Tourist Visa. You’ll have 3 months to use it so will be fine for 10 July. You’ll then get 60 days on entry which you can extend for a further 30 days at an Immigration office in Thailand.
You could start by joining the ‘Jomtien Complex’ and ‘Supertown Jomtien Complex’ groups on FB. They are both run by business owners in the Complex - which is an area in Jomtien with restaurants and gay bars. The area is popular with a lot of people whether gay, straight, male, female etc.
To use the evisa system you’d have to show proof of residency in Spain. You could try applying to the London embassy online but they’ll want to see flights. If you provide a flight to Spain and then a flight from Spain to Thailand you ‘might’ be ok but I’m not sure.
Yes, it does depend on country. UK all online and many others. Still a number of countries don’t use it (eg Australia). You can check on the site if you can use the evisa system or not.