Most physical stores will refuse to use a raw card number without using the chip or tap. The reason is in the card processing agreement, if they use chip or tap, and there is fraud, the bank eats the cost. But for a "card not present" transaction with only a card number, the store has to eat the cost if the transaction is claimed as fraudulent. Most stores will refuse to do transactions like that.

The reason is that the chip is way more secure than a card number, and the banks want to encourage stores to use secure equipment to prevent fraud. The chip creates unique tokens for each transaction so it can't be duplicated. Using the tap with your phone (Google Pay, etc) or card also uses a secure, single use token each time.

P.S. it is possible to install Google Pay on Lineage, at least in some cases. You will have to decide if you are willing to carry cards, or you're willing to install one Google product. You will have to choose one or the other. Or use cash.

No. It may be possible at some places but 99% of the time you'll be told no, and the remaining 1% it's going to be a giant pain in the ass for the clerk or server or bartender.

You should just start using cash.

No.

One alternative to cash might be making use of online ordering with in store pickup, for most takeout and some shopping. Then you'll enter your number on the app or website.

Are you saying, you want the cashier to enter your credit card info manually as you read it to them?