Legal advice on Trademarks

Hi there! I have created a platform for building websites. I planned on giving said platform a specific name, but I had to realize that a competitor already used it in the past. In spite of this, can I still use it? It is worth mentioning that, as far as I know, no trademark has been registered for it and the competitor has since changed its name. I would also like to mention that this is a word taken from the German language, it's not a made-up name. Because I wanted to use a .AI domain for my business, I'd like to register a UK trademark as well. Can there be any problems?

Designed business logo, business cards, an business document samples for a client they didn't pay but are using the samples

I started my home health care business in Indiana under the name Visiting Angels. I enlisted the help of my cousin business Virus LLC to redo my website. They discovered another business with the same name. My cousin suggested I change the name to a simple name Indy Angels. The name IndyAngels.com was available. I changed all my business information (ein's and public profiles) to Visiting Angels dba Indy Angels. I was then contacted by Visiting Angels. I let them know we were already in the process of changing out of Visiting Angels because my cousin already brought this to my attention. I complied and got rid of dba's and everything as I had already had plans to operate solely under Indy Angels. Yet I had wondered how the Secretary of State would allow me to obtain an ein for their same name that had been trademarked. So now I have taken out any trace of Visiting Angels from my business. Now they are contacting me saying because there is a Visiting Angels franchise in Indiana that me using the name Indy Angels is also infringement due to confusion. Others I have asked said there isn't any confusion. I also have seen other home care using the name Angels in it.

I am located in California and there is another business outside California that shares the same business name but in a different industry. My small business is a production company. Their business is a jewelry company. There is however, another company in California that has a similar company name and also operates in the same industry, is that when I should consider to trademark.

A business is already registered in my state as xyz WHOLESALE and I want to register mine with the same first two words, but instead of “WHOLESALE”, mine will say “Goods”. I researched their business and it looks to be related to cargo trailers but my business will sell clothing, accessories, and everyday items. I wonder if this would count as infringement because wholesale is a word that describes one type of way to sell goods, but I’m not sure.

Say I file an ITU and then I'm able to get a specimen a month or two after filing. Can I submit the specimen to speed up the entire process?

How soon will you know if a mark is permitted for use with an ITU vs a standard use in commerce application?

There are currently three registered marks for the card games "Don't Cross Me", "Don't Look At Me!" and "Don't Judge Me". There is also a registered mark for "Don't Quote Me" in the same IC. Are these four names not too similar? Are design elements taken into account for card/board games to further prove a lack of confusion about where they're coming from?

Ex: BODYPLEX vs BODYPLeX vs. bodyplex If I’m using this word and it’s been trademarked in all uppercase letters for Tshirts, but I decide I want to make tshirts using upper and lower case letters with the same word , do I need permission from the owner of the trademark who uses all uppercase letters?

I changed the lyrics and I do not use the whole song, is there any way to make a parody of this (using part of the instrumental version of this song and recording my voice over it)?